JAMB Mathematics Past Questions & Answers - Page 210

1,046.

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

Correct answer is D

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

1,047.

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

A.

72.0

B.

27.0

C.

36.0

D.

3.5

E.

24.5

Correct answer is B

If log\(_9\)x = 1.5,

9\(^1.5\) = x

9^\(\frac{3}{2}\) = x

(√9)\(^3\) = 3

∴ x = 27

1,048.

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

Correct answer is A

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

1,049.

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

Correct answer is A

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

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

= 100.02

1,050.

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

Correct answer is B

-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]