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

### Instruction:
Ivanka wrote a book that took her 3 more months than it took Woody to write a book. Woody spent 1.5 years writing his book. How many months in total did Ivanka and Woody need to write their books?

### Response:
Woody = 1.5 years = 18 months
Ivanka = (18 + 3) months = <<(18+3)=21>>21 months
18 + 21 = <<18+21=39>>39 months
It took Ivanka and Woody 39 months to write their books.
#### 39