Beginning Algebra

A messenger left a construction site and traveled by jeep at 51 km/h. Forty minutes later it was discovered that she had been given the wrong parcel. How fast must a second messenger travel to overtake her in one hour?

First messenger had traveled 2/3 of an hour. In one hour the first messenger would have traveled 68 km/s.

I added 17 to 68 and tht gave me 85. This is the correct answer as stated in the back of the book.

But I didn't use Algebra to get the answer.

Please show me how to set this problem and how to find the answer the correct way.

Thanks

You did good. There are various ways to set it up. One of the easiest may be to consider that the first messenger will have traveled for 5/3 hours before he's caught by the second. While the second is travelling for 1 hour. The second messenger catches the first when their distances are the same.

51(5/3)=r(1). Solve for r. r=85