Let the cost of a shirt be s.
Three shirts = 3s.
3s + 15 ≤ 80 (Answer F)
1 pound = 16 ounces
20 pounds = 320 ounces
320 ounces + 7 ounces = 327 ounces
The speed upstream is the difference between the boat speed and the current speed. It is (12 mi)/(4 h) = 3 mph.
The speed downstream is the sum of the boat speed and the current speed. It is (32 mph)/(4 h) = 8 mph.
The speed of the boat is the average of these: (3 + 8)/2 = 5.5 mph.
The speed of the current is that less the difference: 5.5 - 3 = 2.5 mph.
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<u>Check</u>
Boat + Current = 5.5 + 2.5 = 8 mph
Boat - Current = 5.5 - 2.5 = 3 mph
11/90 hope this helps please give brainliest
