Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
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?

### Response:
The rate is $45 / 3 hours = $<<45/3=15>>15/hr.
She would need to baby-sit for $75 / $15/hr = <<75/15=5>>5 hours.
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