Answer:
32.4 inches
Explanation:
Sam wants the increase to be 8% of 30 inches.
Increase
The amount of increase Sam wants in his waist size is ...
8% × 30 in = 0.08×30 in = 2.4 in
Waist size
Adding the wanted increase to his present size would make Sam's waist size be ...
30 in + 2.4 in = 32.4 in
Sam wants his waist size to be 32.4 inches.
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Additional comment
The larger size can also be computed from ...
30 +8%×30 = (1 +8%)×30 = 1.08×30 = 32.4 . . . inches