Step-by-step explanation:
she increased the amount from 48g to 54g. that is 54-48 = 6g.
so, the question really is, how many % of 48 is 6 ?
100% = 48g
1% = 100%/100 = 48/100 = 0.48g
how many % are 6g ?
as many as how often 1% (0.48g) fits into 6g :
6 / 0.48 = 12.5%