Mathematics questions and answers

Mathematics Questions and Answers

How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.

246.

The height of an equilateral triangle of side is 10 3√ cm. calculate its perimeter.

A.

20cm

B.

60cm

C.

40cm

D.

30cm

Correct answer is B

Height of an equilateral triangle, h = a\(\frac{√3}{2}\), where a is the side of the equilateral triangle.

10√3 = a\(\frac{√3}{2}\)

cross multiply--> 2 * 10√3 = a√3

√3 strikes √3 on both sides

20 = a

The perimeter of an equilateral triangle is: P = 3a

P = 3 * 20 = 60cm

P = 30√3

247.

A trader paid import duty of 38 kobo in the naira on the cost of an engine. If a total of #22,800.00 was paid as import duty, calculate the cost of the engine.

A.

#60,000.00

B.

#120,000.00

C.

#24,000.00

D.

#18,000.00

Correct answer is A

No explanation has been provided for this answer.

248.

make u the subject in x =\(\frac{2u-3}{3u + 2}\)

A.

u = \(\frac{2x + 3}{3x - 2}\)

B.

u = \(\frac{2x - 3}{3x - 2}\)

C.

u = \(\frac{2x + 3}{2 - 3x}\)

D.

u = \(\frac{2x + 3}{3x + 2}\)

Correct answer is C

x =\(\frac{2u-3}{3u + 2}\)

cross multiply

x(3u + 2) = 2u - 3

3ux + 2x = 2u - 3

collect like terms of u

2x + 3 = 2u - 3ux 

\(\frac{2x + 3}{2 - 3x}\) = u

249.

The sum of the interior angles of a regular polygon with k sides is (3k-10) right angles. Find the size of the exterior angle?

A.

60°

B.

40°

C.

90°

D.

120°

Correct answer is A

In a polygon with n sides, the sum of the angles =

(n - 2)180, where n = the number of sides.

In our problem, n = k.

So, we have:

(3k - 10)90 = (k - 2)180

270k - 900 = 180k - 360

Simplifying:

90k = 540

k = 6. So, we have a regular hexagon.

Now, each exterior angle = 360/n

We have: 360/6 = 60

Conclusion: Each exterior angle is 60 degrees.

250.

In the diagram, ∠ABC and ∠BCD are right angles, ∠BAD = t and ∠EDF = 70°. Find the value of t.

A.

70°

B.

165°

C.

140°

D.

110°

Correct answer is D

Vertically opp angles are equal ∠CDE = 70°

Sum of interior angles in a quadilateral = 360°

(90 + 90 + 70 + t)° = 360°

t° = 360° - 250°

t° = 110°