Bob has a certain number of marbles. If he receives 2 dozen more marbles, he will have 60 marbles. If he loses 10 of the marbles he has, how many marbles will Bob have?
Let B be the number of marbles Bob starts with.
2 dozen marbles is 2 * 12 = 
<gadget id="calculator">2*12</gadget>
<output>24</output>
24 marbles.
So after receiving 2 dozen more marbles, we know B + 24 = 60.
This means B = 60 - 24 = 
<gadget id="calculator">60-24</gadget>
<output>36</output>
36.
Bob ends with 36 - 10 = 
<gadget id="calculator">36-10</gadget>
<output>26</output>
26 marbles.

<result>26</result>