Question

Ariel weighed an object on her balance and recorded a mass of 24.3 grams.Her teacher told her that there was 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

For this case what we can do is the following rule of three:
 24.3 -----> 130%
 x ---------> 100%
 We clear the value of x:
 x = (100/130) * (24.3)
 x = 18.7 grams
 Answer:
 the current mass of the object was:
 x = 18.7 grams