1. julia ran and bikes for a total of 40 miles in 5.8 hours. her average running speed was 5.5 mph. her average biking speed was 13.5 mph. let x = total hours julia ran ley y = total hours julia biked use substitution to solve for x and y. show all work. round answers to nearest tenth. a) how many hours did julia run? b) how many hours did julia bike?

Given that Julia ran and bike for a total of 40 miles in 5.8 hours.

Let x be the running time and y be the biking time.

So, x+y=5.8

        y = 5.8 -x ,this is our first equation.

We are also given that average running speed of Julia = 5.5 mph

Distance ran by Julia in x hours = speed * time =5.5x

Given average biking speed of Julia = 13.5mph

Distance  covered by biking in y hours = speed* time = 13.5 y

So total distance covered by julia = 5.5x+13.5y

But given this distance is 40 miles.

That is 5.5x+13.5y = 40

Let us plugin first equation in above step.

5.5x+13.5(5.8-x) = 40

5.5x+78.3-13.5x = 40

78.3-8x = 40

8x = 78.3-40 = 38.3

= 4.8 hours

let us plugin this in our first equation

y= 5.8-x = 5.8-4.7875 = 1.0125 hours = 1.0 hours

a) Julia ran for 4.8 hours

b) Julia biked for 1.0 hours

ege

step-by-step explanation:

egge