7.0
2.56
13.48
2.0
0.07
Correct answer is A
(3.2)2 - (1.8)2 = (3.2 + 1.8)(3.2 - 1.8)
= 5 x 1.4
= 7
5544m2
1386m2
132m2
264m2
693m2
Correct answer is E
\(\pi\) = \(\frac{22}{7}\), Diameter D = 42m
Area of a circle = \(\frac{\pi D^2}{4}\) when a diameter is given
area of a semicircle \(\frac{\pi D^2}{4}\) x \(\frac{1}{2}\)
= \(\frac{22}{7}\) x \(\frac{4262}{4}\) x \(\frac{1}{2}\)
= \(\frac{11}{7} \times 441\)
= 693m\(^{2}\)
\((1.28 \times 10^{4}) \div (6.4 \times 10^{2})\) equals
2 x 10-5
2 x 10-1
2 x 101
2 x 10-4
Correct answer is C
\((1.28 \times 10^{4}) \div (6.4 \times 10^{2})\)
= \(\frac{1.28 \times 10^{4}}{6.4 \times 10^{2}}\)
\(\equiv \frac{12.8 \times 10^{3}}{6.4 \times 10^{2}}\)
= \(2 \times 10^{1}\)
The mean of the numbers 1.2, 1.0, 0.9, 1.4, 0.8, 0.8, 1.2 and 1.1 is
1.5
0.8
1.0
1.02
1.05
Correct answer is E
\(\frac{1.2 + 1.0 + 0.9 + 1.4 + 0.8 + 0.8 + 1.2}{8}\) = \(\frac{8.4}{8}\)
= 1.05
Write the decimal number 39 to base 2
10011 base 2
110111 base 2
111001 base 2
100101 base 2
19.5 base 2
Correct answer is A
\(\begin{array}{c|c} 2 & 39\\ 2 & 19 R 1\\ 2 & 9 R 1\\2 & 4 R 0\\2 & 1 R 0\\ 2 & 1 R 1\end{array}\)
= 10011 base 2