Direct Variation Problems

Write a direct variation equation that relates the two variables. Then solve. Suppose y varies directly as x, and y = 12 when x = 4. Find y when x = 16. The value of y is _____

Write a direct variation equation that relates the two variables. Then solve. Suppose y varies directly as x, and y = 15 when x = 5. Find x when y = 45. The value of x is _____.

Write a direct variation equation that relates the two variables. Then solve. Suppose y varies directly as x, and y = 81 when x = 6. Find x when y = 54.

Write a direct variation equation that relates the two variables. Then solve. Suppose a varies directly as b, and a = 14 when b = 4. Find b when a = 49.

A local fast food restaurant makes $8600 in an 8 hour period. Write a direct variation equation for the relationship between income and number of hours. Estimate how many hours it would take the restaurant to earn $17200.

• 8 hours

• 10 hours

• 12 hours

• 16 hours

A recipe for 5 dozen corn muffins calls for 8 cups of flour. The number of muffins varies directly with the amount of flour you use. Estimate how many cups of flour are needed to make 35 dozen muffins.

• 48 cups

• 48 cups

• 56 cups

• 64 cups

Most pets age at a different rate than their human companions. For example, a 3-year-old dog is often considered to be 21 in human years. Assume that the age of a dog varies directly as its equivalent age in human years. What is the human-year age of a dog that is 6-years-old?

• 28

• 35

• 42

• 49

A person’s weekly pay varies directly with the number of hours worked. Shawn’s pay is $123.00 for 20 hours of work. Find the amount of pay for 31 hours of work.

• $3813

• $190.65

• $4.96

• $620

y varies directly with x. When y = 39,  x = 3.  Find the value of y when x = 2.

• 26

• 3

• 58.5

• 2

The number of pages that Hayden can read varies directly with the time spent reading. If he reads 12 pages in 4 minutes, how many pages can he read in 17 minutes?

• 60 pages

• 51 pages

• 47 pages

• 75 pages