JAMB Mathematics Past Questions & Answers - Page 345

1,721.

In a survey of 50 newspaper readers, 40 read Champion and 30 read Guardian, how many read both papers?

A.

10

B.

5

C.

15

D.

20

Correct answer is D

No explanation has been provided for this answer.

1,722.

Express the product of 0.21 and 0.34 in standard form

A.

7.14 x 10-3

B.

7.14 x 10-2

C.

7.14 x 10-1

D.

7.14 x 10-4

Correct answer is B

0.21 x 0.34 = 0.0714
= 7.14 x 10-2

1,723.

Rationalize \(\frac{2\sqrt{3} + \sqrt{5}}{\sqrt{5} - \sqrt{3}}\)

A.

(3 √ 15 +11) / 2

B.

3 √ 15 -11

C.

(3 √ 15 -11) / 2

D.

3 √ 15 +11

Correct answer is A

\(\frac{2\sqrt{3} + \sqrt{5}}{\sqrt{5} - \sqrt{3}}\)

= \((\frac{2\sqrt{3} + \sqrt{5}}{\sqrt{5} - \sqrt{3}})(\frac{\sqrt{5} + \sqrt{3}}{\sqrt{5} + \sqrt{3}})\)

= \(\frac{2\sqrt{15} + 6 + 5 + \sqrt{15}}{5 - 3}\)

= \(\frac{3\sqrt{15} + 11}{2}\)

1,724.

Evaluate \(\left(\frac{81}{16}\right)^{\frac{-1}{4}}\times 2^{-1}\)

A.

1/3

B.

3

C.

6

D.

1/6

Correct answer is A

\(\left(\frac{81}{16}\right)^{\frac{-1}{4}}\times 2^{-1}=\frac{1}{\left(\frac{81}{16}\right)^{\frac{1}{4}}}\times \frac{1}{2}\\
=\left(\frac{16}{81}\right)^{\frac{1}{4}}\times \frac{1}{2}\\
=\left(\frac{2}{3}\right)^{4\times \frac{1}{4}}\\
=\frac{2}{3}\times \frac{1}{2}\\
=\frac{1}{3}\)

1,725.

Marks 2 3 4 5 6 7 8 9
No. of students 3 4 1 0 4 5 2 1


The table above shows the distribution of marks of students in a test. Find the probability of passing the test if the pass mark is 5?

A.

3
5

B.

2
5

C.

7
20

D.

1
5

Correct answer is A

Total number of students = 20

Marks No. of students
5 0
6 4
7 5
8 2
9 1
  12

 

P(passing)= 12
20

 

 

= 3
5