2009 - JAMB Mathematics Past Questions and Answers - page 6

7\(\frac{1}{12}\) - 4\(\frac{3}{2}\) + 2\(\frac{1}{2}\)

Take care of the whole numbers

7 - 4 + 2 = 5

therefore, 5\(\frac{1}{12}\) - \(\frac{3}{4}\) + \(\frac{1}{2}\)

LCM = 12

5\(\frac{1 - 9 + 6}{12}\)

4\(\frac{13 - 9 + 6}{12}\)

= 4\(\frac{10}{12}\)

or = 4\(\frac{5}{6}\)

\(\frac{81.81 + 99.44}{20.09 + 36.16}\)

= \(\frac{181.25}{56.25}\)

= 3.22

Spent \(\frac{1}{5}\) on books remaining \(\frac{4}{5}\)

spent \(\frac{1}{3}\) of \(\frac{4}{5}\) on food

\(\frac{4}{5}\) x \(\frac{1}{3}\) = \(\frac{4}{15}\)

therefore, \(\frac{4}{5}\) - \(\frac{4}{15}\)

= \(\frac{12 - 4}{15}\)

= \(\frac{8}{15}\)

5^{2(x - 1)} x 5^{x + 1} = 0.04

5^{2x - 1} x 5^{x + 1} = \(\frac{1}{25}\)

5^{3x - 1} = 5^-2

3x - 1= -2

3x = -1

therefore, x = -\(\frac{1}{3}\)

log₁₀(10 x 7 x 4)

log₁₀280 = log₁₀10 + log₁₀7 + 2 log 2

= 1 + 0.8451 + 2(0.3010)

= 2.4471

\(\frac{5 + \sqrt{7}}{3 + \sqrt{7}}\) x \(\frac{3 + \sqrt{7}}{3 + \sqrt{7}}\)

\(\frac{15 - 5 \sqrt{7} + 3\sqrt{7} - 7}{9 - 3\sqrt{7} + 3\sqrt{7} - 7

= 4 - 2\(\sqrt{7}\)

X : (n² + 1) = 2, 5, 10, 17, 26

y : 5n = 5, 10, 15, 20, 25

x ∩ y = (5, 10)

P² = \(\frac{rs^3}{t}\)

P²t = rs³

r = \(\frac{p^2t}{s^3}\)

(3x - 4)(5x + 3)

= 15x² - 11x - 12