SOLUTION: Andrea ran and biked for a total of 32 miles in 4 hours. Her average running speed was 5 mph and her average biking speed was 13 mph. Let x= total hours Andrea ran Let y= total h

Question 1165846: Andrea ran and biked for a total of 32 miles in 4 hours. Her average running speed was 5 mph and her average biking speed was 13 mph.
Let x= total hours Andrea ran
Let y= total hours Andrea bikes
Use substitution to solve for x and y.
a) How many hours did Andrea run?
b) how many hours did Andrea bike?
Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
so total distance on bike was 13y miles
and running is 5x miles
5x+13y=32
x+y=4, so x=4-y
5(4-y)+13y=32
20-5y+13y=32
8y=12
y=1.5 hours on the bike or 19.5 miles
x=2.5 hours running or 12.5 miles
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