Question

Of the 280 muffins that Mr. Parker baked, 40% were corn muffins. How many more corn muffins must Mr. Parker bake so that 60% of the muffin are corn muffins?

Answer 1

56 more muffins

A good place to start is finding the value of 1%.
If 100%=280, then 1%=2.8.
1% times 40%= 40%
2.8 times 40%= 112
1% times 60%= 60%
2.8 times 60%= 168
168-112=56