Post Utme Mathematics Past Questions and Answers

Question 256:

The rate of ice formation in the freezer compartment of a refrigerator is (2-0.3t) g per min; where \(t\) is the time in minutes. If there was initially \(10 \mathrm{~g}\) of ice in the ice-maker, the mass of ice present after 10 minutes is ____________

A. \(5 \mathrm{~g}\)
B. \(10 \mathrm{~g}\)
C. \(15 \mathrm{~g}\)
D. \(25 \mathrm{~g}\)

Question 257:

A die is thrown and a coin is tossed. Find the probability that the die shows an even number and the coin shows a head.

A. \(1 / 4\)
B. \(1 / 6\)
C. \(1 / 2\)
D. 1

Question 258:

If two triangles are similar, then
I. the corresponding angles are equal
II. the corresponding sides are proportional
III. the areas of the triangles are in the same ratio as the lengths of the corresponding sides
IV. the triangles are congruent

Which of the above statements are CORRECT?

A. I and II only
B. IIl and IV only
C. I, II and III only
D. I, III and IV only

Question 259:

A binary operation \(*\) is defined over the set of real numbers such that \(m * n=m+n+2\) and \(m \odot\) \(n=m-n+1\). Which of the following equations is not true?

A. \(a *(b * c)=(a * b * c\)
B. \(a *(b * c)=(a * c) * b\)
C. \(a \odot(b \odot c)=(a \odot b) \odot c\)
D. \(a *(b \odot c)=(a * b) \odot c\)

Question 260:

If \(2 \cos 2 \theta=-\cos \theta\) and \(0<\theta<180^{\circ}\), then \(\theta\) is ____________

A. \(90^{\circ}\) or \(120^{\circ}\)
B. \(60^{\circ}\) or \(90^{\circ}\)
C. \(60^{\circ}\) or \(120^{\circ}\)
D. \(30^{\circ}\) or \(150^{\circ}\)