Jamb Mathematics 1979 Past Questions and Answers

Question 21:

• JAMB 1979

x is directly proportional to y and inversely proportional to z. If x = 9 when y = 24 and z = 8, what is the value of x when y = 5 and z = 6?

A. \(\frac{5}{6}\)
B. 11
C. 3\(\frac{3}{5}\)
D. 2\(\frac{1}{2}\)
E. 1\(\frac{1}{5}\)

Question 22:

• JAMB 1979

The solution of the equation x² - 2x = 8 is

A. X = 0 or 2
B. X = -2 or 4
C. X = 2
D. X = -4
E. X = 2 or 4

Question 23:

• JAMB 1979

A trader goes to Ghana for y days with y cedis. For the first x days, he spends X cedis per day. The amount he has to spend per day for the rest of his stay is

A. \(\frac{y(y - x)}{y - x}\) cedis
B. \(\frac{Yy - Xx)}{y - x}\) cedis
C. \(\frac{Y - Xy)}{y - x}\) cedis
D. \(\frac{Y - X}{y - x}\) cedis
E. \(\frac{Y - Xx}{y - x}\) cedis

Question 24:

• JAMB 1979

Multiply (3x + 5y + 4z) by (2x - 3y + z)

A. 6x² + xy - 15y² + 4z² + 11xz - 7yz
B. 6x² + 3xy - 15y² + 4z²
C. 6x² + 3xy - y² + 4z²
D. 6x² + 3xy - 15y + z²

Question 25:

• JAMB 1979

A square of cardboard is taped at the perimeter by a piece of ribbon 20cm long. What is the area of the board?

A. 20sq.cm
B. 100sq.cm
C. 25sq.cm
D. 16sq.cm
E. 36sq.cm