Let's call x to the original price.
Given that Mason used a 30% coupon, then he paid 0.3x dollars less.
After the discount, the cost of the computer was $728, then
x - 0.3x = 728
0.7x = 728
x = 728/0.7
x = 1040
The original price of the computer was $1040
Mason saves 30% of $1040, which is computed as follows:
[tex]1040\cdot\frac{30}{100}=312[/tex]Mason saves $312