Commerce Solved Objective Test Paper

Commerce  Solved Objective Test  Paper
Commerce Practice Questions With Answers

 STASTICS

1. The difference between the maximum and the minimum observations in the data is

(a) Class interval

(b) Frequency

(c) Cumulative frequency

(d) Range

Ans. (d)

2. The mean wage of 150 labourers working in a factory running three shifts with 60, 40

     and 50 labourers is Rs 114.00. The mean wage of 60 labourers working in the first

     shift is Rs 121.50 and that of 40 labourers working in the second shift is Rs 107.75,

     then the mean wage of those working in the third shift is

(a) Rs 110

(b) Rs 100

(c) Rs 120

(d) Rs 115.75

Ans. (a)

3. Which one of the following is not correct?

(a) Statistics is liable to be misused

(b) The data collected by the investigator to be used by himself are called primary data

(c) Statistical laws are exact

(d) Statistics do not take into account of individual cases

Ans. (c)

4. The statistical data are of two types. These types are

(a) Technical data and presentation data

(b) Primary data and secondary data

(c) Primary data and personal data

(d) None of the above

Ans. (b)

5. The number of times a particular item occurs in a class interval is celled its

(a) Mean

(b) Frequency

(c) Cumulative frequency

(d) None of these

Ans. (b)

6. Kavita obtained 16, 14, 18 and 20 marks (out of 25) in Maths in weekly tests in the

    month of Jan 2000; then mean marks of Kavita is

(a) 16

(b) 16.5

(c) 17

(d) 17.5

Ans. (c)

7. If the mean of x and 1/x is M, then the mean of x² and 1/x² is

(a) M²

(b) M²/4

(c) 2 M²– 1

(d) 2 M² + 1

Ans. (c)

8. A train travels first 300 km at an average rate of 30 km per hour and further travels

      the same distance at an average rate of 60 km per hour, then the average speed over

      the whole distance is

(a) 35 km per hour

(b) 40 km per hour

(c) 42 km per hour

(d) 45 km per hour

Ans. (b)

9. In an examination, a candidate scores the following percentage of marks.

     English — 44; Hindi — 58; Maths — 74; Physics — 61; Chemistry — 62. If weights

     2, 4, 4, 5, 3 respectively allotted to these subjects, then the candidate’s weighted

     mean percentage is

(a) 61

(b) 61.5

(c) 62

(d) 62.5

Ans. (b)

10. The average monthly income of a four members of a family is Rs 610.25, after the

      marriage of one girl the average income of the family becomes Rs 650.75 then the

      salary of married girl is

(a) Rs 488.25

(b) Rs 488.75

(c) Rs 479.75

(d) Rs 489.25

Ans. (b)

11. If the standard deviation for the marks obtained by a student in monthly tests is 36

      then the variance is

(a) 6

(b) 36

(c) 1296

(d) none of these

Ans. (c)

12. The numbers 3, 5, 6 and 4 have frequencies of x, x + 2, x – 8 and x + 6 respectively.

      If their mean is 4 then the value of x is

(a) 5

(b) 6

(c) 7

(d) 8

Ans. (c)

13. The mean of first five prime numbers is

(a) 3

(b) 3.6

(c) 7

(d) 5.6

Ans. (d)

14. If the first five elements of the set x_i + 5, i = 1, 2, 3 ... 5 and the next five elements

     are replaced by x_j - 5, _j = 6... 10 then the mean will change by

(a) 0

(b) 5

(c) 10

(d) 25

Ans. (a)

15. The mean of the following distribution is

      Class           0-5 5-10 10-15 15-20 20-25 25-30

      Frequency    4      5      7         12      7         5

(a) 15

(b) 16

(c) 17

(d) 18

Ans. (b)

16. The attendance of a class of 45 boys for 10 days is given as 40, 42, 30, 35, 45, 44, 41,

      38, 44 and 41 then the mean attendance of a class is

(a) 39

(b) 40

(c) 41

(d) 43

Ans. (b)

17. A school has 20 teachers; one of them retires at the age of 60 years and a new teacher

      Replaces him, this change reduces the average age of the staff by 2 years, the age of

      New teacher is

(a) 28 years

(b) 25 years

(c) 20 years

(d) 18 years

Ans. (c)

18. The ages (in years) of a family of 6 members are 1, 5, 12, 15, 38 and 40. The standard

      deviation is found to be 15.9. After 10 years the standard deviation is

(a) increased

(b) decreased

(c) remains same

(d) none of these

Ans. (c)

19. The average of 15 numbers is 18. The average of first 8 is 19 and that last 8 is 17,

      then the 8th number is

(a) 15

(b) 16

(c) 18

(d) 20

Ans. (c)

20. The arithmetic mean of the set of variable a, a + d, a + 2d, a + 3d . . . a + 2nd is

(a) a + nd

(b) a – nd

(c) (a + n)d

(d) ad + n

Ans. (a)

21. In a class test in English 10 students scored 75 marks, 12 students scored 60 marks, 8

      scored 40 marks and 3 scored 30 marks, the mode for their score is

(a) 75

(b) 30

(c) 60

(d) 25

Ans. (c)

22. The mean of ten items is 17 and if each item is increased by 5, then the new mean

      will be

(a) 22

(b) 67

(c) 17

(d) 85

Ans. (a)

23. The average age of a group of eight is same as it was 3 years ago, when a young

       member is substituted for an old member, the incoming member is younger to the

      outgoing member by

(a) 11 years

(b) 24 years

(c) 28 years

(d) 16 years

Ans. (b)

24. The mean of 20 items of a data is 5 and if each item is multiplied by 3, then the mean

       will be

(a) 5

(b) 10

(c) 15

(d) 20

Ans. (c)

25. The weights of 9 apples are 50, 60, 65, 62, 67, 70, 64, 45, 48 grams. Their mean

      weight is

(a) 60.5 gram

(b) 60 gram

(c) 59 gram

(d) 62 gram

Ans. (c)