Marcy can make 3 spears out of a sapling and 9 spears out of a log. How many spears can she make out of 6 saplings and a log?
First find the total number of spears she makes from saplings: 3 spears/sapling * 6 saplings = 
<gadget id="calculator">3*6</gadget>
<output>18</output>
18 spears.
Then add the number she makes from the log: 18 spears + 9 spears = 
<gadget id="calculator">18+9</gadget>
<output>27</output>
27 spears.

<result>27</result>