human
Alani earned $45 for 3 hours of baby-sitting. At the same rate, for how many hours would she need to baby-sit to earn $75?
assistant
How many dollars does Alani earn per hour? ** The rate is $45/3=$<<45/3=15>>15/hr.
For how many hours would she need to baby-sit to earn $75? ** She would need to baby-sit for $75/$15=<<75/15=5>>5 hours.
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