MODEL TEST PAPER -7(ICSC)

F M: 80                   Time: 2.30 hrs

                     Section A

  (Attempt all questions).   4x10= 40 

1) a) Mr. D. K Vhora gets ₹6455 at the end of a year at the rate of 14% p.a. in a recurring deposit account. Find the monthly installment.

b) Solve the inequation and represent the solution set on the number line -2/3< -x/3 + 1≤2/3; x belongs to R.

c) Solve the following quadratic equation using formula (Correct to three significant figures): x² -3(x+3) = 0.                                        (4+3+3)

2a) Prove the following identity: 

Cosecx/(cosec x -1) + cosecx/(cosecx +1) = 2 sec²x.

b) A box contains 25 cards, numbered from 1 to 25. A card is drawn at random from the box. Find the probability that the number on the card is (i) even ii) Prime iii) multiple of 6.

c) i) Find the mean proportional of 8.1 and 2.5.

ii) Find the third proportion of 21/4 and 7.                                   (3+4+3) 

3a) The point p(3,4) is reflected on p' in the x-axis and o' is the image of o (origin) in the line pp' find: 

i) The coordinates of p' and o'.

ii) The length of the segment pp' and oo'.

iii) The perimeter of the quadrilateral pop'o' (use graph sheet for this question) 

b) If A= 3    4 B= 1     y & C= 7     0

              5     x      0     1        10    5 Find x and y if 2A + B= C.

c) If A=(-4,3), B=(8,-6) in what ratio is the line joining AB, divided by the x-axis ?              (3+4+3) 

4).                                         (4+3+3)

a)Find the mean by shortcut method:

Class interval         frequency 

05-10                           10 

10-15                             6 

15-20                             4 

20-25                            12 

25-30                             8 

30-35                             4 

35-40                             2

40-45                             1

45-50                             3 

b) For what value of k the equation (k -12)(x²+ 2x)+ 2= 0 has equal roots.

c) Find the mode and the median:

x: 10   11   12    13    14     15

f:  1      4      7      5      9        3  

                  SECTION B 

(Attempt only 4)           4x10= 40

5) a) Construct incentre of a triangle ABC, where AB= 6cm, BC= AC = 4cm.

b) Two vertices of a triangle are (3,5) and (-7,4). Find the third vertex, given that the centroid is (2,-1).

c) Is a, b,c are in continued proportion then prove that: (a+ b)/(b+ c) =a²(b - c)/c²(a - b).

6a) 90 pupils in a school have heights as below:  

Height          number of pupils

121-130             12

131-140              6

141-150             30

151-160             20

161-170             14

171-180              8 

Using graph paper draw an ogive and estimate the median and inter quartile range.

b) If cosecx + cot x = p, then prove that cosx= (p²-1)/(p²+1).   (6+4=10)

7)a) Solve the and draw the number line for the following in equation:

3≥ (x -4)/2 + x/3 ≥ 2; x belongs to R.

b) A letter is chosen from the words MONEY DATE. what is the probability that the word is chosen is i) a vowel b) a constant.

c) Find the matrix X If AX = B If 

 A= 4     B= -4       8

       1          -1       2         (4+3+3=10) 

8)a) SOLVE: 16{(a- x)/(a+ x)}³= (a+ x)/(a- x).                       (3+3+4=10)

b) There are two children in a family, find the probability that,

 i) there is at least one girl in the family.

ii) Younger child is a boy. 

c) A two digit number is 4 times the sum and three times the product of its digits. Find the numbers.   

9) Shyam has a cumulative bank account and deposited ₹600 per month for a period of 4 years. If he gets ₹ 5880 as intrest at the time of maturity, find the rate of interest. 

b) Solve:(using formula) 2x - 1/x = 7 (correct to 2 decimal places)

c) Use a graph paper and draw a histogram from the following data, hence estimate mode.

Class interval          Frequency

00-05                           10

05-10                           14

10-15                           28 

15-20                           42 

20-25                           50

25-30                           30 

30-35                           14

35-40                           12      3+3+4 

10).                                           4+3+3

a) Ages of two persons A and B are in the ratio 4:3 five year hence, the ratio of their ages will change to 9:7. Find their present ages.

b) Find X and Y If the relation AB = C where A= X     3X     B= 2     C= 5

                     Y     4Y           1         12

c) Prove: 1 - cos²x/(1+ sin x) = sinx.    

Revision PAPER (X) CBSC

28/11/23

1) If tanx = a/b, then which of the following is the value of (a sinx + b cosx)/+a sinx + b cosx).

a) (a²+ b²)/(a²- b²)

b)  a/√(a²- b²)

c)  b/(a²- b²)

d)  √(a²+ b²)

2) Evaluate: (sinx + cosex)²+ (cosx + Secx)²= tan²x + cot²x +7.

3) If cosecx + cotx = y, find the value of cosx.

4) Eliminate k

x= a seck, y= b tank.

5) If the points (a,0),(0,b) and (1,1) are collinear, then show that 1/a + 1/b =1.

6) A number is chosen at random from the numbers 1,2,...,15. Find the probabilities that the chosen number is

a) even

b) multiple of 3

c) multiple of 4

d) multiple of 3 but not 4

e) multiple of both 3 and 4.

7) In the figure BC= 5cm, 

angle B= 90°, AB= 5AE, CD= 2AE and AC= ED. Find the length of EA, CD, AB, and AC.

8) The wheel of a cart is making 5 revolution per second. If the diameter of the wheel is 84cm, find its speed in kmph. Give your answer, correct to nearest km.

9) The inner dimensions of a closed wooden box are 2m, 1.2m and 0.75m. The thickness of the wood is 2.5cm. find the cost of wood required to make the box if 1 m³ of wood cost &5400.

10) 3) A cylinder is surmounted by a cone at one end and a hemisphere at the other end, Given that common radius=3.5 cm, the height of the cylinder is 6.5 cm and the total height 12.8cm, calculate the volume of the solid correct to the nearest integer. 376 cm³

27/11/23

1) x takes 3 hours more than y to walk 30 km. If x doubles his pace, he is ahead of y by 3/2 hours. Find their speeds of walking.         10/3,5 kmph

2) In a cyclic quadrilateral ABCD, angle A= (2x+4)°, angle B= (y+3)°, angle C= (2y +10)°, angle D= (4x -5)°. Find the four angles.       70,53,110,127

3) 2x+ 3y=7; (k+1)x + (2k -1)y = 4k +1. Find the value of k for which system of equations have infinitely many solution.          5

4) Solve for x,y: a/x - b/y =0; ab²/x + a²b/y = a²+ b², where x,y≠0.           a,b

5) Solve: abx²+ (b²- ac)x - BC= 0.    c/b, -b/a

6) if the equation (1+ m²)x²+ 2mcx + (c²- a²)=0 has equal roots, prove that c²= a²(1+ m²).

7) The length of a hall is 5m more than its breadth . If the area of the floor of the hall is 84 m², what are the length and breadth of the hall ?        7, 12

8) Find the sum of the first 25 terms of an AP, whose nth term is given by aₙ= 7 - 3n.   - 800

9) In figure AB diameter and AC is a chord of a circle such that angle BAC =30°. The tangent at C intersects AB produced in D. Prove that BC= BD.

10) Two chords AB and CD of a circle intersect each other at P outside the circle. If AB =5cm, BP= 3cm and PD =2 cm, find CD.          10cm

11) if x is an acute angle and tanx + cotx=2, find the value tan⁷x + cot⁷x.

12) If A and B are complementary angles, prove that (sinA+ sinB)²= 1+ 2 sinA cosA.

13) A bag contains 5 red balls , 8 white balls, 4 green balls and 7 black balls . If one ball is drawn at random , find the probability that it is

a) black.

b) red 

c) not green

14) What is the probability that a leap year has 53 Sunday and 53 Mondays ?   

15) If r₁ and r₂ be the radii of two solid metallic spheres and if they are melted into one solid sphere, prove that the radius of the new Sphere is (r₁³ + r₂³)¹⁾³.

25/11/23

1) The vertical and slant height of a cone are 24cm and 25cm. Calculate (i) curved surface (ii) volume of the cone.

2) The diameter of an iron sphere is 18cm. The sphere is melted and is drawn into a long wire of uniform cross section. If the length of the wire is 108m. Find its diameter.

3) Find the value of m if (x - m) is a factor of 3x³ + 2x² - 19x + 3m.

4) simplify:2tan 40/cot 50 - cosec 61/sec 29

5) Solve: 4x² - 4ax +(a² - b²) = 0

6) The horizontal distance between two towers is 140m. The angle of elevation of the top of the first tower when seen from the top of the second tower is 30°. If the height of the second tower is 60m. Find the height of the first tower.

7) Prove: 

(1+cosA)/(1-cosA) = (cosecA + cotA)²

8) Find the sum of all multiples of 11 between 100 and 400.            6831

9) How many terms of the series {27+24+21+...} must be added to get the sum 132?            8 or 11

10) Of the point (x,y) be equidistant from the points (a+ b, b - a) and (a - b, a+ b), show that bx = ay.

11) Show (1+ Secx + tanx)(1- cosecx + cotx)= 2.

12) In the figure BOA is a diameter of a circle and the tangent at a point P meets BA extended at T. 

If Angle PBO=30° , then find angle PTA.  90

13) In the figure O is the centre of a circle of radius 5cm,

T is a point such that OT= 13cm and OT intersects the circle at E. If AB is the tangent to the circle at E, find the length of AB.         24

10) Using step deviation method, Calculate the mean of the following frequency distribution:

Class.       Frequency

50-60                9

60-70               11

70-80               10

80-90               14

90-100              8

100- 110          12

110-120           11

12) Draw a histogram and hence estimate the mode for the following frequency distribution:

CLASS- interval.       Frequency

 0-10                               2

10-20                              8

20-30                             10 

30-40                              5

40-50                              4 

50-60                              3

) The marks scored by 40 pupils of a class in a test were as follows:

CLASS: 0 1 2 3 4 5

No. of pupils: 2 4 5 14 11 4

Calculate the mean mark.

MODEL TEST PAPER -6 (ICSE)

1) Mamta has a cumulative Time Deposit Account in a bank. She deposits Rs800 per month and gets Rs15198 as maturity value. If the rate of interest be 7% p.a., find the total time for which the account was held.

2) The vertical and slant height of a cone are 24cm and 25cm. Calculate (i) curved surface and (ii) volume of the cone.

3) The diameter of an iron sphere is 18cm. The sphere is melted and is drawn into a long wire of uniform cross section. If the length of the wire is 108m. Find its diameter.

4) The marks scored by 40 pupils of a class in a test were as follows:

CLASS:            0    1   2    3      4     5

No. of pupils:  2    4   5   14    11   4

Calculate the mean mark.

5) Solve: 2 ≤ 2x - 3 < 5, x belongs R and mark it on the number line.

6) Find the value of m if (x - m) is a factor of 3x³ + 2x² - 19x + 3m.

7)

  If =  -3     2   B= x  C=  -5

           0    -5        2          y and AB= C then find the value of x 

8) What must be added to each of the number 7, 25, 19, and 35 so that the resulting numbers are in proportion ?

9) simplify:

 2tan 40/cot 50 - codec 61/sec 29

10)  Using the remainder theorem, find the remainder when 7x³ + 5x² - 4x - 1 is divided by (x +1).

11) Solve: 4x² - 4ax +(a² - b²) = 0

12) The horizontal distance between two towers is 140m. The angle of elevation of the top of the first tower when seen from the top of the second tower is 30°. If the height of the second tower is 60m. Find the height of the first tower.

13) Find the Equation of a straight line parallel to y-axis  and passing through the point (-3,5).

14) Using step deviation method, Calculate the mean of the following frequency distribution:

Class.       Frequency

50-60                9

60-70               11

70-80               10

80-90               14

90-100              8

100- 110          12

110-120           11

16) Prove: 

(1+cosA)/(1-cosA) = (cosecA + cotA)²

16) Draw a histogram and hence estimate the mode for the following frequency distribution:

CLASS- interval.       Frequency

 0-10                               2

10-20                              8

20-30                             10 

30-40                              5

40-50                              4 

50-60                              3

Quick Revision - IX

Week -1

EXPONENTIAL 

1) Find the value of:

B) 9⁻³ x 16¹⁾⁴/6⁻² x (1/27)⁻⁴⁾³.      8

C) For what value of x, the relation 2ˣ = 3⁻ˣ is true.              When x is 0

D) If (20)²ˣ = 49 then find the value of (20)⁻ˣ.                                    ±1/7

E) If x= 5, y =3 then find the value of (x +y)ˣ⁾ʸ.                                         32

F) Find: (2²ⁿ - 3. 2²ⁿ ²)(3ⁿ⁻² - 2.3²ⁿ⁻²)/{3ⁿ⁻⁴(4ⁿ⁺³ - 2²ⁿ)}.           1/4

G) {(0.3)¹⁾³(1/27)¹⁾⁴(9)¹⁾⁶(0.82)²⁾³}/{(0.9)²⁾³(3)⁻¹⁾²(1/3)⁻²(243)⁻¹⁾⁴}.               3/10

H)  (16)⁻³⁾⁴ x (32)¹⁾⁵ x 5⁰.            1/4

                    

2) Solve:

A)  4ˣ = 8³.          9/2

B) 4ˣ⁺² = 2²ˣ⁺3 +2.        -1

C) 4ˣ - 3.2ˣ⁺² + 2⁵ = 0.     2

D) xʸ = yˣ , x² = y³.       27/8, 9/4

E) 2ˣ⁺² + 2ˣ⁻¹ = 9.                          1

F) 3²ˣ+ 9 = 10. 3ˣ.                    2 or 0

G) 9. 812ˣ = 1/27ˣ⁻².                  4/7

H) 4ˣ⁺² + 2²ˣ⁺³ = 96.                       1

I) 3²ˣ⁻⁵ 9ˣ⁻² = 4.                            5/2

J) 6²ˣ⁺⁴ = 3³ˣ. 2ˣ⁺⁸.                          4

3) Simplify:

(A) xˡ/xᵐ)ˡ⁺ᵐ.(xᵐ/xⁿ)ᵐ⁺ⁿ.(xⁿ/xˡ)ⁿ⁺ˡ.    0

B) {(p² - 1/q²)ᵖ (p - 1/q)ᑫ⁻ᵖ/{(q² - 1/p²)ᑫ (q+ 1/p) ᑫ⁻ᵖ}.           (p/q)ᵖ⁺ᑫ

C) [1- {1- (1- x³)⁻¹}⁻¹]⁻¹⁾³ when x = 0.1.                                                 0.1

D) ⁵√(243)³.                                   27

E) ₓ√x = √(x)ˣ.                             0, 4

F) {(2¹⁾³. 8²⁾³. 6⁻⁵⁾⁴. 3⁻³⁾⁴)/(9⁻¹.³√16)}⁻⁴.                                                    2

G) (9.(4ˣ)²)/(16ˣ⁺¹ - 2ˣ⁺¹. 8ˣ).       9/14

4) Prove: 

A) 1/(1+ xᑫ⁻ᵖ + xʳ⁻ᵖ) + 1/(1+ xᵖ⁻ᑫ + xᑫ⁻ʳᑫ) = 1

B) If aˣ = m, aʸ = n and a²= (mʸˣ)ᶻ then show that xyz = 1.

C) If 64ˣ =48 ʸ = 36ᶻ then prove 1/x + 1/z = 2/y.

D) If 2ᵃ = 3ᵇ = 12ᶜ then prove that ab = c(a+ 2b).

E) If pˣ = qʸ = rᶻ then prove pqr = 1.

F) If aˣ = bʸ = cᶻ and b² = ac, then prove 1/x + 1/z = 2/y.

G) If (3.6)ᵖ =(.36)ᑫ = (1)ʳ then prove 1/p = 1/q + 1/r.

H) If x¹⁾ᵃ = y¹⁾ᵇ = z¹⁾ᶜ and xyz = 1 then prove a+ b + c= 0.

I) If x² = y³ then prove (x/y)³⁾²+ (y/x)²⁾³ = x¹⁾² + y⁻¹⁾³.

J) If xʸ = yˣ then prove that (x/y)ˣ⁾ʸ = xˣ⁾ʸ ⁻¹ .

M) If x¹⁾³ + y¹⁾³+ z¹⁾³ = 0 then prove that (x + y+ z)³ = 27 xyz.

N) If x= 2¹⁾³ + 2⁻¹⁾³ then prove 2x³ = 6x +5.    

O) a= 5 - 5²⁾³ - 5¹⁾³ then prove a³ - 15a² + 60a = 20

MODEL Test paper 5(x) ICSC

    SECTION A (40 MARKS)

Question 1).                   2x5= 10

a) If Ram bought a watch for ₹2688 which includes 12% GST and a shirt for ₹440 which includes 10% GST. Find the printed price of the watch and shirt together, without GST 

b) the point P(a,b) is reflected in the x-axis to obtain the point Q(3,4). Find a, b. 

c) If a    3a        2          5

        b    4b        1 =     12 , find a and b. 

d) The mean of numbers 6,y, 7, x and 14 is 8. express y in terms of x. y= 13 - x 

e) Given f(x) = x/(x² -1). Find f(1/3). 2/3

Question 2.                     10 marks

a) Solve using the quadratic formula x² - 5x - 2= 0. Give your answer correct to 3 significant figures.

b) If (8a+5b)/(8c+5d)= (8a-5b)/(8c - 5d), prove that a/b= c/d

c) Find the value of k, if x- k is a factor of x³ - kx² + x + 4. -4

Question 3              Marks 10

a) Solve 1 < 3x -3≤ 12, x belongs to R and mark it on a number line.     

b) Calculate the mean, median, and mode of the following numbers 11, 12, 10, 11, 12, 13, 14, 13, 15, 13. 

c) Find the sum of the numbers between 2 to 200 divisibile by 4

Question 4             marks 10

a) If cosA= 4/5 and cos B= 24/25 ; evaluate

i) cosec² A. 

ii) cot A + cot B 

b) On a map drawn to a scale of 1:12500 a triangular plot of land has the following measurements: PQ = 10cm, QR= 8cm, Ang PRQ=90° . Calculate 

i) The actual length of PQ in km.

ii) the area of the plot in square kilometre. 

c) Find the probability of extra Sunday in February in leap year

           SECTION B) 40 MARKS

Answer any four questions

Question 5.                    Marks 10

a) The work done by ((2x -- 3) men in (3x+1) days and the work done by (3x+1) men in (x+8) days are in the ratio of 11:15. Find the value of x. 

b) John has a recurring deposit account of ₹1000 per month in a bank. What will he get after 12 months if the rate be 9% p.a

c) Find the mean of the following frequency distribution:

Class Interval. Frequency

         0 - 30                    3

        30-60                     7

        60-90                    15

        90-120                  14

        120-150                  7

        150-180                  4 

Question 6.        Marks 10

a) Two dice are thrown. Find the probability

A) The sum of the scores is 9

B) the product of the score is 12

C) the score on second die is greater than first

D) the sum of the score is a multiple of 4

E) the sum of the score is a perfect square.

b) Prove that: sinA/(1-cotA) + cosA/(1-tanA)= sinA + cosA

Question 7.          Marks 10

a) A straight line passes through the points A(-2,8) and B(10, -4). It intersect the co-ordinates Axes point E and F. P is the midpoint of the segment EF, Find:

I) the equation of the line.

ii) the coordinates of the E and F. 

iii) The coordinates of the point P. 

b) In an auditorium, seats were arranged in rows and columns. The number of rows was equal to the number of seats in each row. When the number of the rows was doubled and the number of seats in each row was reduced by 15, the total number of seats increased by 400. Find 

I) the number of rows in the original arrangement.

ii) the number of seats in the Auditorium after rearrangement. 

Question 8.           Marks 10

a) Draw a histogram and hence estimate the mode for the following frequency distribution

Class Interval. Frequency

         0 - 20                   3

        20- 40                   8

        40- 60                 10

        60- 80                  6

        80-100                 4

       100-120                3 

b) A man standing on the bank of a river observes that the angle of elevation of a tree on the opposite Bank 60°. When he moves 40m away from the bank, he finds the angle of elevation to be 30°. Calculate

I) the width of the river and. 

ii) the height of the tree. 

Question 9.           Marks 10

a) If A=.  4    -2 B= 0    2   C= -2   0

                6    -3       1   -1         1  -3

Find A² - A + BC

b) A vessel is in the form of an inverted cone. Its height is 15cm and the diameter of its top which is open, is 5cm. it is filled with water up to the rim. When lead shot, each of which is a sphere of a diameter 5mm are dropped Into the vessel, 1/3 of the water flows out. Find the number of lead shots dropped into the vessel. 

c) Find the value of k for which the lines my - 7y + 5= 0 and 6x - 2y + 9 = 0 are perpendicular to each other . 

XI MODEL TEST PAPER 2

Question 1.            1x10= 10

i) (i¹⁸ + (1/i)²⁵)³ is
A) 1 B) -1 C) 1 + i D) 2(1- i)

ii) If one root of 2x² - 5x + k= 0 be double the other, find the value of k

A) 2 B) 7 C) 9 D) 25/9

iii) Which term of the series 5, 8, 11, ....is 320 ?

A) 106 B) 110 B) 100 D) 98

iv) How many 9-digits numbers of different digits can be formed?

A) 3298760 B) 3456890

C) 3265920 D) 345690

v) 2³ˣ -1 is divisible by

A) 5 B) 6 C) 7 D) 8

vi) Cos 83 - cos 17 =

A) sin 50 B) sin 33 C) sin 50 sin 33 D) - sin 50 sin 33

vii) If (x+3, y -5) = (5,0) then x and y are

A) 2,5 B) -2,5 C) 2, -5 D) - 2, -5

viii) If f(x)= √x , then the value of f(125)/{f(16)+ f(1)} is

A) 0  B) 1   C) 2     D) none

ix) lim ₓ→₁ {(x²-1)/(x-1)} is

A) 1 B) -1 C) 0 D) 2

x) dy/dx of 1/√x³ is

A) x B) x³ C) 2x³ D) none

Question 2       (2x10)= 20

i) Which term of the progression 19, 91/5, 87/5,......is the first negative term?

ii) Find the coefficient of x⁴ in the expansion of (x/2 - 3/x²)¹⁰

iii) Find the value of cos (15/2)°

iv) There are 3 copies each of 4 different books. Find the number of ways of arranging them on a shelf

v) Value of (cos 10+ sin 20)/(cos 20+ sin 10)

vi) Prove by Induction: 1+5+12+22 +35+....+ n/2 (3n-1)= n²(n +1)/2

Or 

Solve: tanx + sec x =√3

vii) Find the domain and range of (4- x)/(x -4)

viii) lim ₓ→π/2  cotx/(π/2 - x).

ix) Find dy/dx with the help of 1st principal sin x 

OR 

Find dy/dx of cos(sin x²) 

x) The angle between the lines whose slopes are -3 and -1/2

OR

Find the centre and radius of the circle of 2x² + 2y²= 3x - 5y +7.

Question 3                10x3 = 30

i)  Solve: | 1 - i|ˣ = 2ˣ.

OR

 If x be real, Prove that the value of (2x² - 2x +4)/(x² - 4x +3) can not lie between -7 and 1.

ii) The product of first three terms of a GP is 1000. If we add 6 to its second term and 7 to its third term, the resulting three terms form an AP. Find the terms of the GP.

iii) Find the number of words which can be formed by taking two alike and two different letters from the word COMBINATION.

iv) 2 cos a = x + 1/x , Prove 2 cos 2a = x³ + 1/x³

Or

v) Express cos 6x in terms of cos 3x

vi) Solve 3 - 2 cosx - 4 sinx - cos2x + sin2x = 0

vii) If f(x)= log {(1-x)/(1+ x)}, show that f(a) + f(b)= f{(a+ b)/(1+ ab)}.

OR

vii) If y = 1/(a - z) show that dz/dy = (z - a)²

ix) Find the equation of the line joining the origin to the point of intersection of 4x + 3y = 8 and x+ y = 1.

OR

Find the equation of the straight line which passes through the point (4,5) and is perpendicular to the line 3x - 2y +5= 0.

x) Find the Cartesian equation of the curve whose parametric equations is x= t, y= t².

OR

The point diametrically opposite to the point P(1,0) on the circle x² + y² + 2x + 4y - 3= 0 is
A) (3,-4) B) (-3,4) C) (-3,-4) A) (3,4)

Question 4.               4x 5 = 20

i) Two samples of sizes 50 and 100 are given. The mean of these samples are respectively 56 and 50. Find the mean of size 150 by combining.

 ii) Find the standard deviations of

Class: 0-4    4-8     8-12       12-16
F:          4        8         2              1

iii) In Two factories A and B engaged in the same industrial area, the average weekly wages (in rupee) and the standard deviations are as follows:
Factory  Average  S.D   workers
   A            34.5        5        476
   B            28.5       4.5     524
a) Which factory, A or B, pays out a larger amounts as weekly wages?
b) which factory, A or B, has greater variability in individual wages?

iv) Find the value of 8th decile and 75th percentile from the following:
Class.                Frequency
10-14                      3
15-19                      7
20-24                    16
25-29                    12
30-34                     9
35-39                     5

OR

 Determine the mode:
Marks       No. Of students
  00-10              5
10-20              12
29-30              14
30-40              10
40-50               8
50-60.              6