James can make 4 hats out of one yard of velvet. He needs three yards of velvet to make a cloak. How much velvet does he need to make 6 cloaks and 12 hats?
First find the total amount of velvet James uses on the hats: 12 hats / 4 hats/yard = 
<gadget id="calculator">12/4</gadget>
<output>3</output>
3 yards.
Then find the total amount of velvet he needs to make the cloaks: 6 cloaks * 3 yards/cloak = 
<gadget id="calculator">6*3</gadget>
<output>18</output>
18 yards.
Then add those two amounts to find the total amount of velvet he needs: 3 yards + 18 yards = 
<gadget id="calculator">3+18</gadget>
<output>21</output>
21 yards.

<result>21</result>