Convert 3.1415926 to 5 decimal places
3.14160
3.14159
0.31415
3.14200
Correct answer is B
3.1415926 ≊ 3.14159 (to 5 d.p)
13135
21315
43025
11035
Correct answer is A
3310_{5} - 1442_{5} = 1313_{5}
You can either do a direct subtraction (which is easier), or convert both numbers in base 10, subtract and convert back to base 5 (if you're not sure).
Find the standard deviation of the following data -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5
2
3
\sqrt{10}
\sqrt{11}
Correct answer is C
x = \frac{\sum x}{N}
= \frac{0}{11}
= 0
\begin{array}{c|c} x & (x - x) & (x - x)^2 \\\hline -5 & -5 & 25 \\ -4 & -4 & 16 \\-3 & -3 & 9 \\ -2 & -2 & 4 \\ -1 & -1 & 1\\ 0 & 0 & 0\\ 1 & 1 & 1\\ 2 & 2 & 4\\ 3 & 3 & 9\\ 4 & 4 & 16 \\5 & 5 & 25\\ \hline & & 110\end{array}
S.D = \sqrt{\frac{\sum(x - x)^2}{\sum f}}
= \sqrt{\frac{110}{11}}
= \sqrt{10}