John is trying to save money by buying cheap calorie-dense food.  He can buy 10 burritos for $6 that have 120 calories each.  He could also buy 5 burgers that are 400 calories each for $8.  How many more calories per dollar does he get from the burgers?
The burritos have 10*120=
<gadget id="calculator">10*120</gadget>
<output>1_200</output>
1200 calories.
That means he gets 1200/6=
<gadget id="calculator">1200/6</gadget>
<output>200</output>
200 calories per dollar.
The burgers get 5*400=
<gadget id="calculator">5*400</gadget>
<output>2_000</output>
2000 calories.
So he gets 2000/8=
<gadget id="calculator">2000/8</gadget>
<output>250</output>
250 calories per dollar.
So he gets 250-200=
<gadget id="calculator">250-200</gadget>
<output>50</output>
50 more calories per dollar from the burgers.

<result>50</result>