Year : 
2001
Title : 
Mathematics (Core)
Exam : 
JAMB Exam

Paper 1 | Objectives

1 - 10 of 50 Questions

# Question Ans
1.

Evaluate 21.05347 - 1.6324 x 0.43 to 3 decimal places

A. 20.980

B. 20.351

C. 20.981

D. 20.352

Detailed Solution

Hint: Use BODMAS, in other words, do multiplication of the second and the last first before subtracting value obtained from the first.
2.

Simplify \((\sqrt[3]{64a^{3}})^{-1}\)

A. 4a

B. 1/8a

C. 8a

D. 1/4a

Detailed Solution

\((\sqrt[3]{64a^{3}})^{-1} = (\sqrt[3]{(4a)^{3}})^{-1}\)
= \((4a)^{-1} \)
= \(\frac{1}{4a}\)
3.

Given that \(p = 1 + \sqrt{2}\) and \(q = 1 - \sqrt{2}\), evaluate \(\frac{p^{2} - q^{2}}{2pq}\).

A. 2(2+√2)

B. -2(2+√2)

C. 2√2

D. -2√2

Detailed Solution

\(\frac{p^{2} - q^{2}}{2pq} = \frac{(p + q)(p - q)}{2pq}\)
= \(\frac{(1 + \sqrt{2} - (1 - \sqrt{2}))(1 + \sqrt{2} + 1 - \sqrt{2})}{2(1 + \sqrt{2})(1 - \sqrt{2})}\)
= \(\frac{(2\sqrt{2})(2)}{-2}\)
= \(-2\sqrt{2}\)
4.

A car dealer bought a second-hand car for N250,000 and spent N70,000 refurbishing it. He then sold the car for N400,000. What is the percentage gain?

A. 60%

B. 32%

C. 25%

D. 20%

Detailed Solution

Total cost = N(250,000 + 70,000) = N320,000
Selling price = N400,000 (given)
Gain = SP - CP = N(400,000 - 320,000) = N80,000
Gain % = gain/CP x 100 = (80,000/320,000) x 100

Gain % = 25%
5.

If \(x = \frac{y}{2}\),evaluate\(\left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right)\)

A. 5/8

B. 5/2

C. 5/32

D. 5/16

Detailed Solution

\(x = \frac{y}{2} \)
\(\left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right)\)
\(\frac{x^3}{y^3} + \frac{1}{2} = (\frac{y}{2})^{3} \div y^{3} + \frac{1}{2}\)
= \(\frac{y^{3}}{8} \times \frac{1}{y^3} + \frac{1}{2}\)
= \(\frac{1}{8} + \frac{1}{2}\)
= \(\frac{5}{8}\)
\(\frac{1}{2} - \frac{x^2}{y^2} = \frac{1}{2} - (\frac{y}{2})^{2} \div y^2)\)
= \(\frac{1}{2} - \frac{y^2}{4} \times \frac{1}{y^2}\)
= \(\frac{1}{2} - \frac{1}{4}\)
= \(\frac{1}{4}\)
\(\therefore \left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right) = \frac{5}{8} \div \frac{1}{4}\)
= \(\frac{5}{2}\)
6.

Find the principal which amounts to N5,500 at a simple interest in 5 years at 2% per annum.

A. N4,900

B. N5,000

C. N4,700

D. N4,800

Detailed Solution

Principal, P = Amount, A - Interest, I.
A = P + I

I = (P.T.R)/100 = (P x 5 x 2)/100 = 10P/100 = P/10

But A = P + I,
=> 5500 = P + (P/10)
=> 55000 = 10P + P
=> 55000 = 11P

Thus P = 55000/11 = N5,000
7.

Evaluate \(\frac{(0.14^2 \times 0.275)}{7(0.02)}\) to 3 decimal places.

A. 0.039

B. 0.385

C. 0.033

D. 0.038

Detailed Solution

\(\frac{(0.14)^{2} \times 0.275}{7(0.02)} = \frac{(0.14)^{2} \times 0.275}{0.14}\)
= \(0.14 \times 0.275\)
= \(0.0385 \approxeq 0.039\)
8.

Divide: \(a^{3x} - 26a^{2x} + 156a^{x} - 216\) by \(a^{2x} - 24a^{x} + 108\).

A. ax - 2

B. ax + 2

C. ax - 8

D. ax - 6

Detailed Solution

\(\frac{a^{3x} - 26a^{2x} + 156a^{x} - 216}{a^{2x} - 24a^{x} + 108}\)
Let \(a^{x} = z\)
\(\therefore = \frac{z^{3} - 26z^{2} + 156z - 216}{z^{2} - 24y + 108} ... (i)\)
Dividing (i) above, we get \(z - 2\)
= \(a^{x} - 2\)
9.

If two graphs y = px\(^2\) + q and y = 2x\(^2\) -1 intersect at x = 2, find the value of p in terms q.

A. \(\frac{q-8}{7}\)

B. \(\frac{7-q}{4}\)

C. \(\frac{8-q}{2}\)

D. \(\frac{7+q}{8}\)

Detailed Solution

\(y = px^{2} + q ... (i)\)
\(y = 2x^{2} - 1 ... (ii)\)
At x = 2,
(i): \(y = p(2^{2}) + q = 4p + q\)
(ii): \(y = 2(2^{2}) - 1 = 7\)
\(\therefore \text{The coordinates of the point of intersection = (2, 7)}\)
(i): \(7 = 4p + q \implies p = \frac{7 - q}{4}\)
10.

Find the integral values of x and y satisfying the inequality 3y + 5x \(\leq\) 15, given that y > 0, y < 3 and x > 0.

A. (1,1), (1,2), (1,3)

B. (1,1), (2,1), (1,3)

C. (1,1), (3,1), (2,2)

D. (1,1), (1,2), (2,1)

Detailed Solution

Hint: Sketch the inequality graph for the 3 conditions given and read out your points from the co-ordinates.
1.

Evaluate 21.05347 - 1.6324 x 0.43 to 3 decimal places

A. 20.980

B. 20.351

C. 20.981

D. 20.352

Detailed Solution

Hint: Use BODMAS, in other words, do multiplication of the second and the last first before subtracting value obtained from the first.
2.

Simplify \((\sqrt[3]{64a^{3}})^{-1}\)

A. 4a

B. 1/8a

C. 8a

D. 1/4a

Detailed Solution

\((\sqrt[3]{64a^{3}})^{-1} = (\sqrt[3]{(4a)^{3}})^{-1}\)
= \((4a)^{-1} \)
= \(\frac{1}{4a}\)
3.

Given that \(p = 1 + \sqrt{2}\) and \(q = 1 - \sqrt{2}\), evaluate \(\frac{p^{2} - q^{2}}{2pq}\).

A. 2(2+√2)

B. -2(2+√2)

C. 2√2

D. -2√2

Detailed Solution

\(\frac{p^{2} - q^{2}}{2pq} = \frac{(p + q)(p - q)}{2pq}\)
= \(\frac{(1 + \sqrt{2} - (1 - \sqrt{2}))(1 + \sqrt{2} + 1 - \sqrt{2})}{2(1 + \sqrt{2})(1 - \sqrt{2})}\)
= \(\frac{(2\sqrt{2})(2)}{-2}\)
= \(-2\sqrt{2}\)
4.

A car dealer bought a second-hand car for N250,000 and spent N70,000 refurbishing it. He then sold the car for N400,000. What is the percentage gain?

A. 60%

B. 32%

C. 25%

D. 20%

Detailed Solution

Total cost = N(250,000 + 70,000) = N320,000
Selling price = N400,000 (given)
Gain = SP - CP = N(400,000 - 320,000) = N80,000
Gain % = gain/CP x 100 = (80,000/320,000) x 100

Gain % = 25%
5.

If \(x = \frac{y}{2}\),evaluate\(\left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right)\)

A. 5/8

B. 5/2

C. 5/32

D. 5/16

Detailed Solution

\(x = \frac{y}{2} \)
\(\left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right)\)
\(\frac{x^3}{y^3} + \frac{1}{2} = (\frac{y}{2})^{3} \div y^{3} + \frac{1}{2}\)
= \(\frac{y^{3}}{8} \times \frac{1}{y^3} + \frac{1}{2}\)
= \(\frac{1}{8} + \frac{1}{2}\)
= \(\frac{5}{8}\)
\(\frac{1}{2} - \frac{x^2}{y^2} = \frac{1}{2} - (\frac{y}{2})^{2} \div y^2)\)
= \(\frac{1}{2} - \frac{y^2}{4} \times \frac{1}{y^2}\)
= \(\frac{1}{2} - \frac{1}{4}\)
= \(\frac{1}{4}\)
\(\therefore \left(\frac{x^{3}}{y^{3}}+\frac{1}{2}\right) \div \left(\frac{1}{2} - \frac{x^{2}}{y^{2}}\right) = \frac{5}{8} \div \frac{1}{4}\)
= \(\frac{5}{2}\)
6.

Find the principal which amounts to N5,500 at a simple interest in 5 years at 2% per annum.

A. N4,900

B. N5,000

C. N4,700

D. N4,800

Detailed Solution

Principal, P = Amount, A - Interest, I.
A = P + I

I = (P.T.R)/100 = (P x 5 x 2)/100 = 10P/100 = P/10

But A = P + I,
=> 5500 = P + (P/10)
=> 55000 = 10P + P
=> 55000 = 11P

Thus P = 55000/11 = N5,000
7.

Evaluate \(\frac{(0.14^2 \times 0.275)}{7(0.02)}\) to 3 decimal places.

A. 0.039

B. 0.385

C. 0.033

D. 0.038

Detailed Solution

\(\frac{(0.14)^{2} \times 0.275}{7(0.02)} = \frac{(0.14)^{2} \times 0.275}{0.14}\)
= \(0.14 \times 0.275\)
= \(0.0385 \approxeq 0.039\)
8.

Divide: \(a^{3x} - 26a^{2x} + 156a^{x} - 216\) by \(a^{2x} - 24a^{x} + 108\).

A. ax - 2

B. ax + 2

C. ax - 8

D. ax - 6

Detailed Solution

\(\frac{a^{3x} - 26a^{2x} + 156a^{x} - 216}{a^{2x} - 24a^{x} + 108}\)
Let \(a^{x} = z\)
\(\therefore = \frac{z^{3} - 26z^{2} + 156z - 216}{z^{2} - 24y + 108} ... (i)\)
Dividing (i) above, we get \(z - 2\)
= \(a^{x} - 2\)
9.

If two graphs y = px\(^2\) + q and y = 2x\(^2\) -1 intersect at x = 2, find the value of p in terms q.

A. \(\frac{q-8}{7}\)

B. \(\frac{7-q}{4}\)

C. \(\frac{8-q}{2}\)

D. \(\frac{7+q}{8}\)

Detailed Solution

\(y = px^{2} + q ... (i)\)
\(y = 2x^{2} - 1 ... (ii)\)
At x = 2,
(i): \(y = p(2^{2}) + q = 4p + q\)
(ii): \(y = 2(2^{2}) - 1 = 7\)
\(\therefore \text{The coordinates of the point of intersection = (2, 7)}\)
(i): \(7 = 4p + q \implies p = \frac{7 - q}{4}\)
10.

Find the integral values of x and y satisfying the inequality 3y + 5x \(\leq\) 15, given that y > 0, y < 3 and x > 0.

A. (1,1), (1,2), (1,3)

B. (1,1), (2,1), (1,3)

C. (1,1), (3,1), (2,2)

D. (1,1), (1,2), (2,1)

Detailed Solution

Hint: Sketch the inequality graph for the 3 conditions given and read out your points from the co-ordinates.