Paper grade distribution

There are 28 pupils in the class. Twenty-seven of them wrote the control paper in mathematics. Four students had a one, 8 had a two, 12 students had a three, and 3 had a four. Express this distribution as a percentage.

Final Answer:

a =  14.2857 %
b =  28.5714 %
c =  42.8571 %
d =  10.7143 %
e =  3.5714 %

Step-by-step explanation:

$$\begin{gathered} n=28 \\ a=100\cdot \frac{4}{n}=100\cdot \frac{4}{28}=\frac{100\cdot 4}{28}=\frac{400}{28}=14.2857\% \end{gathered}$$

$b=100\cdot \frac{8}{n}=100\cdot \frac{8}{28}=\frac{100\cdot 8}{28}=\frac{800}{28}=28.5714\%$

$c=100\cdot \frac{12}{n}=100\cdot \frac{12}{28}=\frac{100\cdot 12}{28}=\frac{1200}{28}=42.8571\%$

$d=100\cdot \frac{3}{n}=100\cdot \frac{3}{28}=\frac{100\cdot 3}{28}=\frac{300}{28}=10.7143\%$

$e=100\cdot \frac{n-27}{n}=100\cdot \frac{28-27}{28}=3.5714\%$

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