Sarah has 9 books and Joseph had twice the number of Sarah’s books, but he lost 2 of them. How many books does Joseph currently have?
Joseph used to have 9 books * 2 = 
<gadget id="calculator">9*2</gadget>
<output>18</output>
18 books.
After he lost 2 books he remained with 18 books - 2 books = 
<gadget id="calculator">18-2</gadget>
<output>16</output>
16 books.

<result>16</result>