Post a New Question

math

posted by on .

Phil is making a 40-kilometer canoe trip. If he travels at 30 kilometers per hour for the first 10 kilometers, and then at 15 kilometers per hour for the rest of the trip, how many minutes more will it take him then if he travels the entire trip at 20 kilometers per hour?

  • math - ,

    >he travels at 30 kilometers per hour for the first 10 kilometers
    It takes 10/30 = 1/3 hour = 20 minutes

    >at 15 kilometers per hour for the rest of the trip
    The rest of the trip = 40-10=30km,
    which takes 30/15=2 hours
    So, in total the first option takes 2 hours and 20 minutes or 2 1/3 hours.

    The second option:
    >he travels the entire trip at 20 kilometers per hour
    40/20=2 hours

    >how many minutes more will it take
    2 1/3 - 2 =1/3 hour = 20 minutes

    see you at ascii_org_ru

  • math - ,

    time = distance/speed

    10/30 + 30/15 = 2 1/3
    40/20 = 2

    so, it takes 1/3 hour (20 minutes) more.

Answer This Question

First Name:
School Subject:
Answer:

Related Questions

More Related Questions

Post a New Question