Question

A certain cake recipe states that the cake should be bake in a pan 8 inches in diameter. Of jules wants to use the recipe to make a cake of the same depth but 12 inches in diameter, by what factor should he multiply the recipe ingredients

Answer 1

Area factor is in question here!

The factor is area of cake with 12 inches diameter divide by area of cake with 8 inches diameter

Area = Pi times radius squared

For cake with 12 inches diameter, the area = Pi times 6^2

For cake with 8 inches diameter, area = Pi times 4^2

Area factor = (Pi times 36) / (Pi times 16) = 36/16 = 2.25

He should multiply the recipe ingredients by 2.25