SOLUTION: Help please. I think I know the equation, but not sure. I think the equation is Speed = distance/time Brenda and her husband Randy bicycled cross-country together. One mornin

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Question 76895: Help please. I think I know the equation, but not sure. I think the equation is Speed = distance/time
Brenda and her husband Randy bicycled cross-country together. One morning Brenda rode 30 miles. By traveling only 5 miles per hour faster and putting in one more hour, Randy coverd twice the distance Brenda covered. What was the speed of each cyclist?

Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!

Help please. I think I know the equation, but not sure. 
think the equation is Speed = distance/time 
Brenda and her husband Randy bicycled cross-country together.
One morning Brenda rode 30 miles. By traveling only 5 miles 
per hour faster and putting in one more hour, Randy covered
twice the distance Brenda covered. What was the speed of 
each cyclist?

Make this chart:

        DISTANCE   RATE    TIME
Brenda   
Randy   

>>...Brenda rode 30 miles...<<

>>...Randy covered twice the distance Brenda covered...<<

So fill in 30 for Brenda's distance and twice that, or 60
for Randy's distance:


        DISTANCE   RATE    TIME
Brenda   30         
Randy    60       

Let x be Brenda's rate (speed). Fill that in

        DISTANCE   RATE    TIME
Brenda   30         x     
Randy    60      


>>...By traveling only 5 miles per hour faster...Randy...<<

So fill in Randy's speed as x+5


        DISTANCE   RATE    TIME
Brenda   30         x      
Randy    60        x+5    

Now use TIME = DISTANCE/RATE to fill in the rest of the
chart:

        DISTANCE   RATE    TIME
Brenda   30         x      30%2Fx
Randy    60        x+5    60%2F%28x%2B5%29

To make the equation, we look to see what we haven't used:

>>...putting in one more hour, Randy...<< 

So Randy's time = Brenda's time + 1 hour

60%2F%28x%2B5%29+=+30%2Fx+%2B+1

Can you solve that?  If not post again asking how.

Answer: x = 10

So Brenda's speed = x = 10mph
Randy's speed = x+5 = 10+5 = 15mph.

Edwin