STATISTICS - Jamb Mathematics Past Questions and Answers

Question 86:

• JAMB 1981

Marks scored by some children in an arithmetic test are:5, 3, 6, 9, 4, 7, 8, 6, 2, 7, 8, 4, 5, 2, 1, 0, 6, 9, 0, 8.
The arithmetic mean of the marks is

A. 6
B. 5
C. 8
D. 7
E. 10

Question 87:

• JAMB 1981

The weights of 30 new-born babies are given as follow: 6, 9, 5, 7, 6, 7, 5, 8, 9, 5, 7, 5, 8, 7, 8, 7, 5, 6, 5, 7, 6, 9, 9, 7, 8, 8, 7, 8, 9, 8. The mode is

A. 6
B. 5
C. 8
D. 7
E. 10

Question 88:

• JAMB 1981

7 pupils of average age 12 years leave a class of 25 pupils of average age 14 years. If 6 new pupils of average age 11years join the class, what is the average age of the pupils now in the class?

A. 13years
B. 12 years 7\(\frac{1}{2}\) months
C. 13 years 5 months
D. 13 years 10 months
E. 11 years

Question 89:

• JAMB 1982

Find the median of the set set of numbers 110, 116, 113, 119, 118, 127, 118, 117, 113

A. 117.5
B. 118
C. 117
D. 116
E. 113

Question 90:

• JAMB 1982

Determine the mean monthly salary of 50 employees of a company from the following frequency distribution.
\(\begin{array}{c|c} \text{Monthly salary} & \text{Frequency}\\\hline N200.00 & 10\\ N325.00 & 5\\N100.00 & 20\\N120.00 & 2\\ N60.00 & 10\\ N80.00 & 3\end{array}\)

A. N215.30
B. N134.10
C. N143.10
D. N80.00
E. N50.30