1994 - JAMB Mathematics Past Questions and Answers - page 1

(\frac{1}{3} \div [\frac{5}{7}(\frac{9}{10} -1 + \frac{3}{4})])

(\frac{1}{3} \div [\frac{5}{7}(\frac{9}{10} - \frac{10}{10} + \frac{3}{4})])

= (\frac{1}{3} \div [\frac{5}{7}(\frac{-1}{10} + \frac{3}{4})])

= (\frac{1}{3} \div [\frac{5}{7}(\frac{-2 + 15}{20})])

= (\frac{1}{3} \div [\frac{5}{7} \times \frac{13}{20}])

(\frac{1}{3} + [\frac{13}{28}]) = (\frac{1}{3} \times \frac{28}{13})

= (\frac{28}{39})

(\frac{0.36 \times 5.4 \times 0.63}{4.2 \times 9.0 \times 2.4})

= (\frac{36}{420} \times \frac{54}{90} \times \frac{63}{240})

= (\frac{6}{70} \times \frac{18}{30} \times \frac{21}{80})

= (\frac{27}{2000})

= 0.0135

(\approx) = 0.013

(\frac{log_5 0.04}{log_3 18 - log_3 2})

= (\frac{log_5 0.04}{log_3(\frac{18}{2})})

= (\frac{log_5 0.04}{log_3 9})

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

= -1

Let log₅ 0.04 = x

5x = 0.04

x = (\frac{4}{100}) = 5^-2

Let log₃ 9 = z

3² = 3²

z = 3

8x^-2 = (\frac{2}{25})

= 200x^-2 = 2

= 100x^-2 = 1

x^-2 = (\frac{1}{100})

x^-2 = 10^-2

x = 10

(\sqrt{48}) - (\frac{9}{\sqrt{3}}) + (\sqrt{75})

Rearrange = (\sqrt{48}) + (\sqrt{75}) - (\frac{9}{\sqrt{3}})

= (√16 x √3) + (√25 x √3) - (\frac{9}{\sqrt{3}})

=4√3 + 5√3 - (\frac{9}{\sqrt{3}})

Rationalize (\to) 9√3 = (\frac{9}{\sqrt{3}}) x (\frac{\sqrt{3}}{\sqrt{3}})

= (\frac{9\sqrt{3}}{\sqrt{9}}) - (\frac{9\sqrt{3}}{\sqrt{3}})

= 3√3

(\frac{1}{\sqrt{2}}) = (\frac{1}{\sqrt{2}}) x (\frac{\sqrt{2}}{\sqrt{2}})

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

= (\frac{1.414}{2})

= 0.707

A (\subset) B means A is contained in B i.e. A is a subset of B(A (\cap) B)¹ = A¹

A(A (\cap) B)¹ = A (\cap) A¹

The intersection of complement of a set P and P¹ has no element

i.e. n(A (\cap) A¹) = (\phi)

(\frac{(2m - u)^2 - (m - 2u)^2}{5m^2 - 5u^2})

= (\frac{2m - u + m - 2u)(2m - u - m + 2u)}{5(m + u)(m - u)})

= (\frac{3(m - u)(m + u)}{5(m + u)(m - u)})

= (\frac{3}{5})