Matt can make a batch of a dozen cookies using 2 pounds of flour.  He uses 4 bags of flour each weighing 5 pounds.  If Jim eats 15 cookies how many cookies are left?
Matt used 4*5=
<gadget id="calculator">4*5</gadget>
<output>20</output>
20 pounds of flour.
That means he made 20/2=
<gadget id="calculator">20/2</gadget>
<output>10</output>
10 batches.
So he cooked 10*12=
<gadget id="calculator">10*12</gadget>
<output>120</output>
120 cookies.
After Jim eats 15 there are 120-15=
<gadget id="calculator">120-15</gadget>
<output>105</output>
105 cookies left.

<result>105</result>