Class IX Math
MCQ for Statistics
1. Find the mean of x + 77, x + 7, x + 5, x + 3 and x – 2?
(a) x + 8
(b) x + 18
(c) x – 8
(d) x – 18
2. If the mean of n observations x
1, x
2, x
3, .... xn is
(a) 0
(b) 1
(c) 2
(d) 3
3. If each observation of the data is increased by 5, then what happens to its mean?
(a) is increased by 4
(b) is increased by 5
(c) is decreased by 4
(d) is decreased by 5
4. In the class intervals 40 – 50, 50 – 60, the number 50 is included in which of the following?
(a) 40 – 50
(b) 30 – 40
(c) 50 – 60
(d) 60 – 70
5. If the mean of x, x + 3, x + 5, x + 7 and x + 10 is 9 then what is the means of last three observations?
(a)
(b)
(c)
(d) 12
6. If x be the mid-point and 1 be the upper class limit of a class in a containous frequency distribution. What is the lower limit of the class?
(a) x – 1
(b) 3x + 8
(c) 2x + 2
(d) 2x – 1
7. The mean of five numbers is 30. If one number is excluded, their mean becomes 28. What is the excluded number?
(a) 38
(b) 35
(c) 33
(d) 36
8. What is the median of the data 78, 56, 22, 34, 45, 54, 39, 68, 54, 84?
(a) 54
(b) 53
(c) 55
(d) 51