Evaluate: \(\frac{0.21 \times 0.072 \times 0.00054}{0.006 \times 1.68 \times 0.063}\)
0.01286
0.01285
0.1286
0.1285
Correct answer is A
\(\frac{0.21 \times 0.072 \times 0.00054}{0.006 \times 1.68 \times 0.063}\)
= \(\frac{9 \times 10^{-10}}{7 \times 10^{-8}}\)
= \(1.2857 \times 10^{-2}\)
= \(0.012857 \approxeq 0.01286\) (to 4 s.f)
Simplify \((\sqrt{0.7} + \sqrt{70})^{2}\)
84.7
70.7
217.7
168.7
Correct answer is A
\((\sqrt{0.7} + \sqrt{70})^{2}\)
= \((\sqrt{0.7} + \sqrt{70})(\sqrt{0.7} + \sqrt{70})\)
= \(0.7 + 2\sqrt{0.7 \times 70} + 70\)
= \(0.7 + 14 + 70 \)
= 84.7
Simplify 52.4 - 5.7 - 3.45 - 1.75
41.4
41.5
42.1
42.2
Correct answer is B
52.4 - 5.7 - 3.45 - 1.75
= 52.4 - (5.7 + 3.45 + 1.75)
= 52.4 - 10.90
= 41.5
95
80
125
110
Correct answer is D
Hint: Represent the question in a venn diagram, such that
n(B ∩ M) = x
n(B) only = 125-x
n(M) only = 110-x
=> 125-x + 110-x + x = 220
=> x = 15.
n(B) only = 125 - 15 = 110
Without using tables, evaluate \((343)^{\frac{1}{3}} \times (0.14)^{-1} \times (25)^{-\frac{1}{2}}\)
10
12
8
7
Correct answer is A
\((343)^{\frac{1}{3}} \times (0.14)^{-1} \times (25)^{-\frac{1}{2}}\)
= \(\sqrt[3]{343} \times (\frac{14}{100})^{-1} \times (\sqrt{25})^{-1}\)
= \(7 \times \frac{100}{14} \times \frac{1}{5}\)
= 10.