A frying pan, grill or griddle holds a few pancakes, burgers or flatbreads at a time, and every one needs cooking on both sides. The student works out the shortest time to cook them all, or the most that can be cooked in a given number of minutes.
Cooking in batches wastes space in the pan. Counting sides instead gives the answer: the total number of sides divided by how many fit in the pan, rounded up, and keeping the pan full every go always achieves it. The working shows the plan go by go.

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