A. 60%, because 10 % of $50 is $5. Therefore, the difference is 30 from 80-50.
Meaning there was $30 increase.
30/5 = 6*10= 60
Therefore it is 60%.
B. 10% of 28 is 2.8, so take that multiple 2.8 by 2.5 times which you will get $7,
From there add 7 + 28 and you will get 35.
So the price of the new shirt is $35.