WAEC 2022 · Paper 1 · Q45

Statistics: data & averages

The mean of two numbers $x$ and $y$ is 4. Find the mean of the four numbers $x$ , $2x$ , $y$ and $2y$ .

Worked solution (try it first)

The mean of $x$ and $y$ is 4, so $x + y = 2 \times 4 = 8$ .
The four numbers add up to $x + 2x + y + 2y = 3(x + y) = 24$ .
Their mean is $\frac{24}{4} = 6$ , option C.

Report a problem with this question