Direct variation - Jamb Mathematics Past Questions and Answers

Question 16:

• JAMB 2010

W is directly proportional to U. If W = 5 when U = 3, find U when W = \(\frac{2}{7}\)

A. \(\frac{6}{35}\)
B. \(\frac{10}{21}\)
C. \(\frac{21}{10}\)
D. \(\frac{35}{6}\)

Question 17:

• JAMB 2011

If x varies directly as square root of y and x = 81 when y = 9, Find x when y = 1\(\frac{7}{9}\)

A. 20\(\frac{1}{4}\)
B. 27
C. 2\(\frac{1}{4}\)
D. 36

Question 18:

• JAMB 2012

If y varies directly as \(\sqrt{n}\) and y = 4 when n = 4, find y when n = 1\(\frac{7}{9}\)

A. \(\sqrt{17}\)
B. \(\frac{4}{3}\)
C. \(\frac{8}{3}\)
D. \(\frac{2}{3}\)

Question 19:

• JAMB 2014

y varies directly as w². When y = 8, w = 2. Find y when w = 3

A. 18
B. 12
C. 9
D. 6

Question 20:

• JAMB 2015

The extension of a stretched string is directly proportional to its tension. If the extension produced by a tension of 8 Newton’s is 2cm, find the extension produced by a tension of 12 newton’s.

A. 2
B. 1
D. 3