If 16 bananas cost 2.40 how much would 20 cost?

Answer 1

The cost per banana is $2.40 divided by 16 = 15 cents each. So 20 would cost $3.00.

Another way to calculate this is that 20 is 4 more than 16, and so would cost 1/4 as much as another 16, giving $2.40 + 0.60 = $3.00.