Jamb Mathematics 1980 Past Questions and Answers

Question 16:

• JAMB 1980

Make c the subject of formula v = 1 - \(\frac{a}{5}\)(b + \(\frac{3c}{7}\))

A. [\(\frac{7}{3}\) + \(\frac{5}{a}\)(v - 1)] + b
B. [\(\frac{7b}{3}\) + \(\frac{5}{a}\)(v - 1)]
C. \(\frac{7}{3}\)[b + \(\frac{5}{a}\)(v - 1)]
D. \(\frac{7}{3}\)[b + \(\frac{5v - 1}{a}\)]

Question 17:

• JAMB 1980

What factor is common to all the expressions x² - x, 2x² + x - 1 and x² - 1?

A. X
B. X + 1
C. X - 1
D. No common factor
E. (2x - 1)

Question 18:

• JAMB 1980

Which of the formula below represents the general terms of the following set of numbers(-1, \(\frac{2}{3}\), -\(\frac{1}{2}\), \(\frac{2}{5}\)......) for n = 1, 2, 3, 4.......?

A. \(\frac{2}{n + 1}\)
B. (-1)^{n + 1} \(\frac{2}{n + 1}\)
C. (-1)ⁿ \(\frac{2}{n + 1}\)
D. \(\frac{n}{2n - 1}\)
E. (-1)ⁿ\(\frac{n}{2n - 1}\)

Question 19:

• JAMB 1980

Three numbers, x, y and z are connected by the relationships y = \(\frac{4x}{9}\) + 1. If x = 99, find z

A. 6\(\frac{1}{3}\)
B. 20
C. 21
D. 176\(\frac{4}{9}\)
E. None of the above

Question 20:

• JAMB 1980

In a school, there are 35 students in class 2A and 40 in class 2B. The mean score for class 2 in an English Literature examination is 60.0 and that for 2B in the same paper is 52.5. Find, to one place of decimal, the mean for the combined classes

A. 2.5
B. 56.0
C. 56.2
D. 56.3
E. 6.5