Uriah's book bag is getting too heavy for him. He needs to remove 15 pounds from it. His comic books weigh 1/4 pound each and his toys weigh 1/2 pound each. If he removes 30 comic books, how many toys does he need to remove?
30 comic books weigh 7.5 pounds because 30 x .25 = 
<gadget id="calculator">30*.25</gadget>
<output>7.5</output>
7.5.
He needs to remove 7.5 more pounds because 15 - 7.5 = 
<gadget id="calculator">15-7.5</gadget>
<output>7.5</output>
7.5.
He needs to remove 15 toys because 7.5 / .5 = 
<gadget id="calculator">15</gadget>
<output>15</output>
15.

<result>15</result>