Answer:
4 sets
Step-by-step explanation:
406 - 278 = 128
1 set = 40
2 sets = 80
3 sets = 120
4 sets = 160
3.2 sets = 128
$5 each car
3 hours = 12 cars
÷3 ÷3
1 hours = 4 cars
×8 ×8
8 hours = 32 cars
32 cars × $5 per car =
$160
They earned $160 in 8 hours, from washing 32 cars.
3,360
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