Question

Gisele trains 7 days per week for a biathlon. She covers a total of 20 miles cycling and running each day. Gisele cycles a total of 105 miles each week, and runs a certain number of miles per week. If she cycles the same number of miles each day and runs the same number of miles each day, the equation 1/7 (105+r) = 20 represents the situation. Which describes the solution, r to this equation?

A The solution is 5, which represents the number of miles she runs each day.
B The solution is 5, which represents the number of miles she runs each week.
C The solution is 35, which represents the number of miles she runs each day.
D The solution is 35, which represents the number of miles she runs each week

Answer 1

The answer is D

The solution is 35, which represents the number of miles she runs each week.

Answer 2

D The solution is 35, which represents the number of miles she runs each week.

Explanation:

Given that Gisele trains 7 days a week, the total of miles she cycles and runs in a week can be divided by 7, or multiplied by 1/7 to find her daily average. Her total number of miles ran for the week combined with her cycling miles multiplied by 1/7 would average 20 miles daily. Since the run is the same each day, using the equation:

1/7(105 + r) = 20 will give the value of 'r' in the number of miles ran per week

105 + r = 140 (multiply both sides by '7')

r = 35 (subtract '105' from both sides)