Answer
$20\bar{0}0$
Work Step by Step
To solve the given equation for $m$, we multiply both sides by $2$ and then divide both sides by $v^2$ as follows
$$
E=\frac{mv^2}{2}\Longrightarrow 2 E= mv^2 \Longrightarrow m=\frac{2E}{v^2}
.$$
Now, by substitution, we have
$$
m=\frac{2E}{v^2}=\frac{2\times 484,000}{22^2}=20\bar{0}0
.$$
