Proportion Application

Question

 If a 40-pound bag of fertilizer covers 5000 square feet, how many pounds of fertilizer are needed to cover an area of 26,000 square feet?

Answer 1

Hi Sophie,

When 2 ratios/rates are equivalent, we say they form a proportion. In this problem, we can compare the weight of fertilizer to the are covered for each situation. The variable x will represent the weight of fertilizer needed for 26000 square feet:

40 pounds = x

5000 square feet 26000 square feet

Since 5000 times 5.2 is 26000, we can multiply the numerator and denominator by 5.2 to find the value of x

40 pounds • 5.2 = 208 pounds

5000 square feet • 5.2 26000 square feet

You will need 208 pounds of fertilizer for 26000 square feet.