Year : 
1985
Title : 
Mathematics (Core)
Exam : 
JAMB Exam

Paper 1 | Objectives

1 - 10 of 47 Questions

# Question Ans
1.

If three numbers P, Q, R are in ratio 6 : 4 : 5, find the value of \(\frac{3p - q}{4q + r}\)

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

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

C. 2

D. 3

E. 18

Detailed Solution

P : Q : r = 6 : 4 : 5

5 = 6 + 4 + 5

= 15

P = \(\frac{6}{15}\), q = \(\frac{4}{15}\), r = \(\frac{5}{15}\) = \(\frac{1}{3}\)

To find \(\frac{3p - q}{4q + r}\)

3p - q = 3 x \(\frac{6}{15}\) - \(\frac{4}{15}\)

\(\frac{18}{15}\) - \(\frac{4}{15}\) = \(\frac{14}{15}\)

∴ 4q + r = 4 x \(\frac{4}{15}\) + \(\frac{5}{15}\)

\(\frac{16}{15}\) = \(\frac{16}{15}\) + \(\frac{5}{15}\)

= \(\frac{21}{15}\)

\(\frac{14}{15}\) x \(\frac{15}{21}\) = \(\frac{14}{21}\)

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

Arrange the following numbers in ascending order of magnitude \(\frac{6}{7}\), \(\frac{13}{15}\), 0.8650

A. \(\frac{6}{7}\) < 0.865 < \(\frac{13}{15}\)

B. \(\frac{13}{15}\) < \(\frac{6}{7}\) < 0.865

C. \(\frac{6}{7}\) < \(\frac{13}{15}\) < 0.865

D. 0.865 < \(\frac{6}{7}\) < \(\frac{13}{15}\)

Detailed Solution

\(\frac{6}{7}\), \(\frac{13}{15}\), 0.8650

In ascending order, we have 0.8571, 0.8650, 0.8666

i.e. \(\frac{6}{7}\) < 0.8650 < \(\frac{13}{15}\)
3.

A sum of money was invested at 8% per annum simple interest. If after 4 years the money amounts to N330.00. Find the amount originally invested

A. N180.00

B. n165.00

C. N150.00

D. N250.00

E. N200.00

Detailed Solution

S.I = \(\frac{PTR}{100}\)

T = 4yrs, R = 8%, a = N330.00

330 - P = \(\frac{PTR}{100}\), A = P + I

i.e. A = P + \(\frac{PTR}{100}\)

330 = P + \(\frac{P(4) (8)}{100}\)

33000 = 32P + 100p

132P = 33000

P = N250.00
4.

In the equation below, Solve for x if all the numbers are in base 2: \(\frac{11}{x}\) = \(\frac{1000}{x + 101}\)

A. 101

B. 11

C. 110

D. 111

E. 10

Detailed Solution

\(\frac{11}{x}\) = \(\frac{1000}{x + 101}\) = 11(x + 101)

1000x = 11x + 1111

1000x - 11x = 1111

101x = 1111

x = \(\frac{1111}{101}\)

x = 11
5.

List all integers satisfying the inequality -2 \(\leq\) 2 x -6 < 4

A. 2, 3, 4, 5

B. 2, 3, 4

C. 2, 5

D. 3, 4, 5

E. 4, 5

Detailed Solution

-2 \(\leq\) 2x - 6 < 4 = 2x - 6 < 4

= 2x < 10

= x < 5

2x \(\geq\) -2 + 6 \(\geq\)

= x \(\geq\) 2

∴ 2 \(\leq\) x < 5 [2, 3, 4]
6.

Find correct to two decimals places 100 + \(\frac{1}{100}\) + \(\frac{3}{1000}\) + \(\frac{27}{10000}\)

A. 100.02

B. 1000.02

C. 100.22

D. 100.01

E. 100.51

Detailed Solution

100 + \(\frac{1}{100}\) + \(\frac{3}{1000}\) + \(\frac{27}{10000}\)

\(\frac{1000,000 + 100 + 30 + 27}{10000}\) = \(\frac{1,000.157}{10000}\)

= 100.02
7.

John gives one-third of his money to Janet who has N105.00. He then finds that his money is reduced to one-fourth of what Janet now has. Find how much money john has at first

A. N45.00

B. N48.00

C. N52.00

D. N60.00

E. N52.00

Detailed Solution

Let x be John's money, Janet already had N105, \(\frac{1}{3}\) of x was given to Janet

Janet now has \(\frac{1}{3^2}\)x + 105 = \(\frac{x + 315}{3}\)

John's money left = \(\frac{2}{3}\)x

= \(\frac{\frac{1}{4}(x + 315)}{3}\)

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

24x = 3x + 945

∴ x = 45
8.

Find x if log\(_9\)x = 1.5

A. 72.0

B. 27.0

C. 36.0

D. 3.5

E. 24.5

Detailed Solution

If log\(_9\)x = 1.5,
9\(^1.5\) = x
9^\(\frac{3}{2}\) = x
(√9)\(^3\) = 3

∴ x = 27
9.

Write h in terms of a, b, c, d if a = \(\frac{b(1 - ch)}{a - dh}\)

A. h = \(\frac{a - b}{ad}\)

B. h = \(\frac{1 - b}{ad - bc}\)

C. h = \(\frac{(a - b)^2}{ad - bc}\)

D. h = \(\frac{a - b}{ad - bc}\)

E. h = \(\frac{b - a}{ab - dc}\)

Detailed Solution

a = \(\frac{b(1 - ch)}{a - dh}\)

a = \(\frac{b - bch}{1 - dh}\)

= a - adh

= b - bch

a - b = bch + adn

a - b = adh

a - b = h(ad - bc)

h = \(\frac{a - b}{ad - bc}\)
10.

22\(\frac{1}{2}\)% of the Nigerian Naira is equal to 17\(\frac{1}{10}\)% of a foreign currency M. What is the conversion rate of the M to the Naira?

A. 1M = 1\(\frac{15}{57}\)N

B. 1M = 38\(\frac{1}{4}\)N

C. 1M = 1\(\frac{18}{57}\)N

D. 1M = 384\(\frac{3}{4}\)N

Detailed Solution

N = 22\(\frac{1}{2}\)%, M = 17\(\frac{1}{10}\)%

M = \(\frac{171}{10}\)%, N = \(\frac{45}{2}\)

\(\frac{45}{2}\) x \(\frac{10}{171}\)

= \(\frac{225}{171}\)

= 1 \(\frac{54}{171}\)

= 1 \(\frac{18}{57}\)
1.

If three numbers P, Q, R are in ratio 6 : 4 : 5, find the value of \(\frac{3p - q}{4q + r}\)

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

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

C. 2

D. 3

E. 18

Detailed Solution

P : Q : r = 6 : 4 : 5

5 = 6 + 4 + 5

= 15

P = \(\frac{6}{15}\), q = \(\frac{4}{15}\), r = \(\frac{5}{15}\) = \(\frac{1}{3}\)

To find \(\frac{3p - q}{4q + r}\)

3p - q = 3 x \(\frac{6}{15}\) - \(\frac{4}{15}\)

\(\frac{18}{15}\) - \(\frac{4}{15}\) = \(\frac{14}{15}\)

∴ 4q + r = 4 x \(\frac{4}{15}\) + \(\frac{5}{15}\)

\(\frac{16}{15}\) = \(\frac{16}{15}\) + \(\frac{5}{15}\)

= \(\frac{21}{15}\)

\(\frac{14}{15}\) x \(\frac{15}{21}\) = \(\frac{14}{21}\)

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

Arrange the following numbers in ascending order of magnitude \(\frac{6}{7}\), \(\frac{13}{15}\), 0.8650

A. \(\frac{6}{7}\) < 0.865 < \(\frac{13}{15}\)

B. \(\frac{13}{15}\) < \(\frac{6}{7}\) < 0.865

C. \(\frac{6}{7}\) < \(\frac{13}{15}\) < 0.865

D. 0.865 < \(\frac{6}{7}\) < \(\frac{13}{15}\)

Detailed Solution

\(\frac{6}{7}\), \(\frac{13}{15}\), 0.8650

In ascending order, we have 0.8571, 0.8650, 0.8666

i.e. \(\frac{6}{7}\) < 0.8650 < \(\frac{13}{15}\)
3.

A sum of money was invested at 8% per annum simple interest. If after 4 years the money amounts to N330.00. Find the amount originally invested

A. N180.00

B. n165.00

C. N150.00

D. N250.00

E. N200.00

Detailed Solution

S.I = \(\frac{PTR}{100}\)

T = 4yrs, R = 8%, a = N330.00

330 - P = \(\frac{PTR}{100}\), A = P + I

i.e. A = P + \(\frac{PTR}{100}\)

330 = P + \(\frac{P(4) (8)}{100}\)

33000 = 32P + 100p

132P = 33000

P = N250.00
4.

In the equation below, Solve for x if all the numbers are in base 2: \(\frac{11}{x}\) = \(\frac{1000}{x + 101}\)

A. 101

B. 11

C. 110

D. 111

E. 10

Detailed Solution

\(\frac{11}{x}\) = \(\frac{1000}{x + 101}\) = 11(x + 101)

1000x = 11x + 1111

1000x - 11x = 1111

101x = 1111

x = \(\frac{1111}{101}\)

x = 11
5.

List all integers satisfying the inequality -2 \(\leq\) 2 x -6 < 4

A. 2, 3, 4, 5

B. 2, 3, 4

C. 2, 5

D. 3, 4, 5

E. 4, 5

Detailed Solution

-2 \(\leq\) 2x - 6 < 4 = 2x - 6 < 4

= 2x < 10

= x < 5

2x \(\geq\) -2 + 6 \(\geq\)

= x \(\geq\) 2

∴ 2 \(\leq\) x < 5 [2, 3, 4]
6.

Find correct to two decimals places 100 + \(\frac{1}{100}\) + \(\frac{3}{1000}\) + \(\frac{27}{10000}\)

A. 100.02

B. 1000.02

C. 100.22

D. 100.01

E. 100.51

Detailed Solution

100 + \(\frac{1}{100}\) + \(\frac{3}{1000}\) + \(\frac{27}{10000}\)

\(\frac{1000,000 + 100 + 30 + 27}{10000}\) = \(\frac{1,000.157}{10000}\)

= 100.02
7.

John gives one-third of his money to Janet who has N105.00. He then finds that his money is reduced to one-fourth of what Janet now has. Find how much money john has at first

A. N45.00

B. N48.00

C. N52.00

D. N60.00

E. N52.00

Detailed Solution

Let x be John's money, Janet already had N105, \(\frac{1}{3}\) of x was given to Janet

Janet now has \(\frac{1}{3^2}\)x + 105 = \(\frac{x + 315}{3}\)

John's money left = \(\frac{2}{3}\)x

= \(\frac{\frac{1}{4}(x + 315)}{3}\)

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

24x = 3x + 945

∴ x = 45
8.

Find x if log\(_9\)x = 1.5

A. 72.0

B. 27.0

C. 36.0

D. 3.5

E. 24.5

Detailed Solution

If log\(_9\)x = 1.5,
9\(^1.5\) = x
9^\(\frac{3}{2}\) = x
(√9)\(^3\) = 3

∴ x = 27
9.

Write h in terms of a, b, c, d if a = \(\frac{b(1 - ch)}{a - dh}\)

A. h = \(\frac{a - b}{ad}\)

B. h = \(\frac{1 - b}{ad - bc}\)

C. h = \(\frac{(a - b)^2}{ad - bc}\)

D. h = \(\frac{a - b}{ad - bc}\)

E. h = \(\frac{b - a}{ab - dc}\)

Detailed Solution

a = \(\frac{b(1 - ch)}{a - dh}\)

a = \(\frac{b - bch}{1 - dh}\)

= a - adh

= b - bch

a - b = bch + adn

a - b = adh

a - b = h(ad - bc)

h = \(\frac{a - b}{ad - bc}\)
10.

22\(\frac{1}{2}\)% of the Nigerian Naira is equal to 17\(\frac{1}{10}\)% of a foreign currency M. What is the conversion rate of the M to the Naira?

A. 1M = 1\(\frac{15}{57}\)N

B. 1M = 38\(\frac{1}{4}\)N

C. 1M = 1\(\frac{18}{57}\)N

D. 1M = 384\(\frac{3}{4}\)N

Detailed Solution

N = 22\(\frac{1}{2}\)%, M = 17\(\frac{1}{10}\)%

M = \(\frac{171}{10}\)%, N = \(\frac{45}{2}\)

\(\frac{45}{2}\) x \(\frac{10}{171}\)

= \(\frac{225}{171}\)

= 1 \(\frac{54}{171}\)

= 1 \(\frac{18}{57}\)