Re: word problems

Posted by T.Gracken on September 17, 2002 at 07:55:05:

In Reply to: word problems posted by Suzi on September 16, 2002 at 22:57:22:

: We need help with my son's math - On a recent 6 hour bike trip of 70 miles, Lila spent 2 hours on the first part of the trip where her average speed was half of her average speed on the second part. What was her speed on the first part? We have been given the answer which is 7 miles/hour. We must set up the problem. Any help???

Here's another look (different view) at what Mr. B did.

let "r" equal the average rate on the first part of the trip. then "2r" is the average rate on the second part of the trip.

now, (average rate) times (time traveled) equal (distance traveled)

so, first part of trip: distance = 2r

and, second part of trip: distance = 4*2r = 8r

now, add the distances together to get 2r + 8r = 70

so 10r = 70

so r = 7.

since all units were miles or hours, the rate is 7 miles per hour.

Follow Ups:

• Wow, you simplified it, Mr G: ain't teachers suppose to complicate ? :) Denis Borris 11:09:12 09/17/02 (1)
  • sorry... I'll try harder on the next one -nt- T.Gracken 11:44:43 09/17/02 (0)

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