A storekeeper increased the price of hats by 5%. Write an equation to calculate the increase of the total cost, c, when the price of a hat is p dollars.

c = 1.05p

Step-by-step explanation:

the price of the hat before the increase was 100%, after the increase it becomes 100 + 5% = 105%. Representing it as a decimal becomes 1.05p

Let illustrate with an example.

The price of a hat was $100, after the 5% increase. the cost of the hat becomes

100 + (0.05 x 100) = 105

To find the percentage increase

divide 105 by 100 and subtract 1

(105/100) - 1 = 1.05