Elective Mathematics

Question 1

1The standard deviation of a data set is

Easy

A. the range divided by 2 B. the square of the variance C. the mean of the data D. the square root of the variance

Question 2

2If each value in a data set is increased by 5, the standard deviation

Medium

A. increases by 5 B. stays the same C. decreases by 5 D. doubles

Question 3

3The interquartile range is

Easy

A. Q3 − Q1 B. Q3 + Q1 C. Q2 − Q1 D. max − min

Question 4

4Find the variance of 2, 4 and 6.

Medium

A. 8 B. 8/3 C. 4 D. 16/3

Question 5

5The mean of five numbers is 12. Four of them are 10, 14, 8 and 16. Find the fifth.

Easy

A. 48 B. 10 C. 60 D. 12

Question 6

6The class mark of the interval 10–19 is

Easy

A. 10 B. 14.5 C. 19 D. 15

Question 7

7The standard deviation of a data set is 4. If each value is multiplied by 3, the new standard deviation is

Hard

A. 36 B. 12 C. 7 D. 4

Question 8

8To estimate the mean of grouped data, each class is represented by its

Easy

A. frequency only B. upper boundary C. mid-point (class mark) D. width

Question 9

9The variance of 1, 3, 5 is

Easy

A. 2 B. 8/3 C. 3 D. 4

Question 10

10The coefficient of variation of data with mean 50 and SD 5 is

Hard

A. 250% B. 10% C. 5% D. 45%