Jamb Mathematics 1981 Past Questions and Answers

Question 26:

• JAMB 1981

Two cars X and Y start at the same point and travel towards a point P which is 150km away. If the average speed of Y is 60km per hour and x arrives at P 25 minutes earlier than Y. What is the average speed of X?

A. 51\(\frac{3}{7}\)km per hour
B. 72km per hour
C. 37\(\frac{1}{2}\) km per hour
D. 66km per hour
E. 75km per hour

Question 27:

• JAMB 1981

simplify \(\frac{6^{2n + 1} \times 9^n \times 4^{2n}}{18^n \times 2^n \times 12^{2n}}\)

A. 3²ⁿ
B. 3 x 2^{3n - 1}
C. 2ⁿ
D. 6
E. 1

Question 28:

• JAMB 1981

The number 25 when converted from the tens and units base to the binary base (base two) is one of the following

A. 10011
B. 111011
C. 111000
D. 11001
E. 110011

Question 29:

• JAMB 1981

Evaluate \(\frac{6.3 \times 10^5}{8.1 \times 10^3}\) to 3 significant fiqures

A. 77.80
B. 778.0
C. 7.870
D. 8.770
E. 88.70

Question 30:

• JAMB 1981

The positive root of t in the following equation, 4t2 + 7t - 1 = 0, correct to 4 places of decimal, is

A. 1.0622
B. 10.6225
C. 0.1328
D. 0.3218
E. 2.0132