The total distance travelled by the boat is 12 miles
Distance 1 = 8 mph × 3/4 h
= (8 × 3) / 4
= 24/3
= 8 miles
Distance 2 = 12 mph × 1/3 h
= (12 × 1) / 3
= 12/3
= 4 miles
Total distance = Distance 1 + Distance 2
= 8 miles + 4 miles
= 12 miles
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