<p>As part of an active exercise program, Nora rode her bicycle at a speed of 15 miles per hour for a certain distance. She then jogged an identical distance at a speed of 5 miles per hour. If her entire workout took two hours, what was the TOTAL distance Nora covered cycling and jogging?</p>
<p>thnks</p>
<p>distance=rate x time
distance biking = 15x (x=hrs spent biking)
distance jogging = 5(2-x)</p>
<p>15x=5(2-x)
15x=10-5x
20x=10
x=.5hrs (i.e. 30 mins)</p>
<p>Now plug in x in either original function
15(.5)=7.5
OR
5(2-.5)=7.5</p>
<p>Nora biked 7.5 miles and then jogged 7.5 miles, so she covered a total of
Ans: 15 miles</p>
<p>Thnks so much</p>
<p>Yeah, you can do this a number of ways.
I just set up two different time variables.
d=15t1
d=5t2
t1+t2=2
15t1=5t2
t2=3t1
t1+3t1=2
4t1=2
t1=1/2
The rest is pretty much self explanatory.</p>
<p>or just use the xiggi method......... n(rate1 x rate2)/(rate1 + rate 2)</p>
<p>^^ stephennn what does "n" represent? if it represent the # of hours, then you have to double what you get from using that formula</p>
<p>Here's how I would approach the problem without using variables--an intuitive approach.</p>
<p>She bikes three times as fast as she jogs and she went the same distance each time, so she was biking for one fourth of the time, or 30 minutes. So her distance is the same as if she biked for one hour at 15 miles per hour. Obviously, the answer is 15 miles.</p>
<p>yeah, i did it the intuitive way also</p>