DELSU Mathematics 2020/2021 Past Questions

Practice each question, then open it to see the full details.

The angle of depression of two points A and B on a plane field from the top of a mast erected between A and B are 30° and 45° respectively. If A is westward of B, find |AB| if the height of the mast is 15m from the field.

A.15√3m
B.5(3 + √3)m
C.15(1 + √3)m
D.15(√3 - 1)m

The radius if a circle is given as 10cm subject to an error of 0.2cm. The error in the area of the circle is

A.1⁄4%
B.1⁄50%
C.2%
D.4%

In a survey of 100 students in an institution, 80 students speak Yoruba, 22 speak Igbo, while 6 speak neither Igbo nor Yoruba. How many students speak Yoruba and Igbo?

A.96
B.8
C.64
D.12

A bag contains 5 yellow balls, 6 green and 9 black balls. A ball is drawn from the bag. What is the probability that it is a black or yellow ball?

A.37/160
B.133/400
C.77/800
D.133/800

The expression a³ + b³

A.(a² + b)(a - ab - b²)
B.(a + b)(a² - ab + b²)
C.(a - b²)(a² - ab + b)
D.(a - b)(a² + ab + b²)

Find T if S = 2r√(p)(QT + K)

A.T = S² - 4pr²K/4r²PQ
B.T = S² - 4prK/4pr²
C.T = S² - 4pr²K/4pr
D.T = S² - tprK/4pQ

Calculate each exterior angle of a regular polygon

A.82°
B.108°
C.80°
D.72°