Problema Solution
Dru is constructing a bridge. It takes 12 cubic yards of concrete to make a bridge that is 4 inches thick. Write a direct variation equation that relates c and t, where c is cubic yards and t is thickness in inches
Answer provided by our tutors
When two variable quantities have a constant (unchanged) ratio, their relationship is called a direct variation.
The constant ratio is called the constant of variation.
The formula for direct variation is y = kx, where k is the constant of variation.
In our case we have:
k = 12/4
k = 3
The direct variation equation is:
c = 3t