Answer
a) $52.9\%$
b) $52.86\%$
Work Step by Step
a) To round to the nearest tenth, inspect the digit in the hundredths position.
$52.8\underset\uparrow647\%$$\Rightarrow$ since $\geq5$, round up
$52.8647\%\approx52.9\%$
b) To round to the nearest hundredth, inspect the digit in the thousandths position.
$52.86\underset\uparrow47\%$$\Rightarrow$ since $\lt5$, round down
$52.8647\%\approx52.86\%$