NECO Mathematics Past Questions & Answers - Page 27

131.

A quadratic equation with roots -1\(\frac{1}{2}\) and \(\frac{1}{4}\) is

A.

x2 + 3x + 4 = 0

B.

8x2 + 10x + 3 = 0

C.

8x2 +12x – 3 = 0

D.

8x2 + 10x-3.= 0

E.

8x2 + 12x + 3 = 0

Correct answer is D

No explanation has been provided for this answer.

132.

One bag contains 4 white balls and 2 black balls. Another bag contains 3 white balls and 5 black balls, if one ball is drawn from each bag, what is the probability that both are white?

A.

\(\frac{2}{3}\)

B.

\(\frac{3}{8}\)

C.

\(\frac{7}{24}\)

D.

\(\frac{1}{4}\)

E.

\(\frac{1}{24}\)

Correct answer is D

No explanation has been provided for this answer.

133.

A wire was shaped to form a square of area 81cm\(^2\). An equilateral triangle was formed by the same wire,What is the length of a side of the triangle formed?

A.

3cm

B.

6cm

C.

9cm

D.

12cm

E.

27cm

Correct answer is D

Area of a square = L X L = 81

: L = 9

Perimeter of square = 4 X L 

 4 X 9 = 36cm

An equilateral triangle with equal sides:

 36/3 = 12cm

134.

What is the total surface area of a cylinder with radius 2cm and height 1.5cm, correct to 2 significant figures?

A.

440cm\(^2\)

B.

220cm\(^2\)

C.

88cm\(^2\)

D.

44cm\(^2\)

E.

22cm\(^2\)

Correct answer is D

T.S.A of a cylinder = \(2\pi r (r + h)\)

= \(2 \times \frac{22}{7} \times 2 (2 + 1.5)\)

= 44 cm\(^2\)

135.

The probability that a student will pass a mathematics test is ⅗. If 3 students are chosen at random, what is the probability that at least 2 of them will pass the test?

A.

\(\frac{27}{125}\)

B.

\(\frac{9}{25}\)

C.

\(\frac{72}{125}\)

D.

\(\frac{76}{125}\)

E.

\(\frac{81}{125}\)

Correct answer is E

No explanation has been provided for this answer.