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.

2,601.

\(\begin{array}{c|c}
Class Interval & 3 - 5 & 6 - 8 & 9 - 11 \\ \hline Frequency & 2 & 2 & 2 \end{array}\). Find the standard deviation of the above distribution.

A.

√5

B.

√6

C.

√7

D.

√2

Correct answer is B

\(\begin{array}{c|c}Class Interval & 3 - 3 & 6 - 8 & 9 - 11 \\ x & 4 & 7 & 10 \\ f & 2 & 2 & 2 \\ f - x & 8 & 14 & 20 \\ |x - \bar{x}|^2 & 9 & 0 & 9 \\ |x - \bar{x}|^2 & 18 0 & 18 \end{array}\)

\(\bar{x}\) = \(\frac {\sum fx}{\sum f}\)

= \(\frac {8 + 14 + 20}{2 + 2 + 2}\)

= \(\frac{42}{6}\)

\(\bar{x}\) = 7

S.D = \(\sqrt\frac{\sum f(x - \bar{x})^2}{\sum f}\)

= \(\sqrt\frac{18 + 0 + 18}{6}\)

= \(\sqrt\frac{36}{6}\)

= \(\sqrt {6}\)

2,602.

\(\begin{array}{c|c} No & 0 & 1 & 2 & 3 & 4 & 5 \\ \hline Frequency & 1 & 4 & 3 & 8 & 2 & 5 \end{array}\). From the table above, find the median and range of the data respectively.

A.

(8,5)

B.

(3, 5)

C.

(5 , 8)

D.

(5 , 3)

Correct answer is B

Median = \(\frac{\sum fx}{\sum f}\)

\(\begin{array}{c|c}
No & 0 & 1 & 2 & 3 & 4 & 5 \\ F & 1 & 4 & 3 & 8 & 2 & 5 \\ fx & 0 & 4 & 6 & 24 & 8 & 25 \end{array}\)

\(\sum fx\) = 0 + 4 + 6 + 24 + 8 + 25 = 67

\(\sum f\) = 23

Median = \(\frac{\sum fx}{\sum f}\) = \(\frac{67}{23}\) = 2.913

= \(\approx\) 3

Range = 5 - 0 = 5

(3, 5)

2,603.

The sum of four consecutive integers is 34. Find the least of these numbers

A.

7

B.

6

C.

8

D.

5

Correct answer is A

Let the numbers be a, a + 1, a + 2, a + 3

a + a + 1 + a + 2 + a + 3 = 34

4a = 34 - 6

4a = 28

a = \(\frac{28}{4}\)

= 7

The least of these numbers is a = 7

2,604.

Find \(\int\) cos4 x dx

A.

\(\frac{3}{4}\) sin 4x + k

B.

-\(\frac{1}{4}\) sin 4x + k

C.

-\(\frac{3}{4}\) sin 4x + k

D.

\(\frac{1}{4}\) sin 4x + k

Correct answer is D

\(\int\) cos4 x dx

let u = 4x

\(\frac{dy}{dx}\) = 4

dx = \(\frac{dy}{4}\)

\(\int\)cos u. \(\frac{dy}{4}\) = \(\frac{1}{4}\)\(\int\)cos u du

= \(\frac{1}{4}\) sin u + k

= \(\frac{1}{4}\) sin4x + k

2,605.

Evaluate \(\int^{1}_{0}\)(3 - 2x)dx

A.

33m

B.

5

C.

2

D.

6

Correct answer is C

\(\int^{1}_{0}\)(3 - 2x)dx

[3x - x\(^2\)]\(_{0} ^{1}\)

[3(1) - (1)\(^2\)] - [3(0) - (0)\(^2\)]

(3 - 1) - (0 - 0) = 2 - 0

= 2