Question

Ariel weighed an object on her balance and recorded a mass of 24.3 grams. Her teacher told her that there was obviously something wrong with her balance because it was giving her a reading which was 30.0% too high. What was the actual mass of the object?

Answer 1

$100\% - 30\% = 70\%$
$24.3 \times 70\% \\ = 24.3 \times \frac{70}{100} \\ = 17.01$
The actual mass was 17.01 grams.

Hope this helps. - M