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5 votes
25 points!!!! (you have to solve both part a AND part b)

PART A:
My friend sets out walking at a speed of 3 miles per hour. I set out behind her 5 minutes later at 4 miles per hour.

When I start walking, how many miles has my friend traveled?

PART B:
My friend sets out walking at a speed of 3 miles per hour. I set out behind her 5 minutes later at 4 miles per hour.

For how many minutes will my friend have been walking when I catch up to her?

User Liesl
by
6.0k points

2 Answers

4 votes
PART A AND B ARE BOTH ANSWERED AT THE END OF THE QUESTION:)convert her walking speed from mph to feet per hour.
3 times 5,280=15,840 feet---her speed per hour.
15,840/60=264 feet-----her speed per minute
THEREFORE: 5 times 264=1,320 feet----that she walked when you started, or: 1,320/5,280=1/4 of a mile she walked in 5 minutes.

Part B)
User Paul Lindner
by
6.4k points
2 votes
Part A:

60/3= 20

You travel 1 mile every 20 minutes.

So, 5 minutes is 1/4 of 20.

Your friend walked 1/4 of a mile.

Part B:

You already know that your friend was 1/4 mile ahead of you.

She will continue to walk at the same rate.

You will walk:

6/4= 15

1 mile every 15 minutes.

Every 5 minutes, you walk a 1/3 of a mile.

(this is distance walking every 5 minutes)
Friend/ You

1/4 0

2/4 1/3

3/4 2/3

4/4 3/3


4/4= 1 and 3/3

Your friend will have walked 20 minutes before you caught up with her.

I hope this helps!
~kaikers
User Dirtyvagabond
by
6.7k points