or
or
A car washer machine can wash 8 cars in 18 minutes. How marry cars can be washed at the same rate in 3 hours?
3 hours = 180 minutes
In 18 minutes car washer washes 8 cars
In 1 minutes car washer washes 8/18 cars
In 180 minutes car washer washes (8*180)/18 = 80 cars
