waecmaths question:
If 30% of y is equal to x, what, in terms of x is 30% of 3y
Option A:
$\tfrac{x}{9}$
Option B:
$\tfrac{x}{3}$
Option C:
x
Option D:
3x
waecmaths solution:
$\begin{align} & \frac{30}{100}\times y=x \\ & \frac{3y}{10}=x \\ & y=\frac{10x}{3} \\ & \therefore 3y=\frac{10x}{3}\times 3=10x \\\end{align}$
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