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?
Woody = 1.5 years = 18 months.
Ivanka = 18 + 3 = 
<gadget id="calculator">18+3</gadget>
<output>21</output>
21 months
18 + 21 = 
<gadget id="calculator">18+21</gadget>
<output>39</output>
39 months.
It took Ivanka and Woody 39 months to write their books.

<result>39</result>