The scale drawing of a deck that Mr. Ford is building measures 15 cm by 21 cm. Each 3 cm on the scale drawing equals 5 feet. What are the actual dimensions of the deck?

To find the actual dimensions of the deck, we first need to find the scale factor between the scale drawing and the actual dimensions.

Given that each 3 cm on the scale drawing equals 5 feet, we can calculate the scale factor as follows:

Scale factor = 5 feet / 3 cm = 5/3

Now, we can find the actual dimensions of the deck by multiplying the dimensions of the scale drawing by the scale factor:

Actual length = 21 cm * (5/3) = 35 feet
Actual width = 15 cm * (5/3) = 25 feet

Therefore, the actual dimensions of the deck that Mr. Ford is building are 35 feet by 25 feet.