Merry had 50 boxes of apples on Saturday and 25 boxes on Sunday. There were 10 apples in each box. If she sold a total of 720 apples on Saturday and Sunday, how many boxes of apples are left?
Merry had a total of 50 + 25 = 
<gadget id="calculator">50+25</gadget>
<output>75</output>
75 boxes of apples.
These 75 boxes is equal to 75 x 10 = 
<gadget id="calculator">75*10</gadget>
<output>750</output>
750 apples.
There were 750 - 720 = 
<gadget id="calculator">750-720</gadget>
<output>30</output>
30 apples left.
Thus, 30/10 = 
<gadget id="calculator">30/10</gadget>
<output>3</output>
3 boxes of apples are left.

<result>3</result>