math
posted by Larry .
Phil is making a 40kilometer 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 
noname
>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 = 4010=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 
Steve
time = distance/speed
10/30 + 30/15 = 2 1/3
40/20 = 2
so, it takes 1/3 hour (20 minutes) more.
Respond to this Question
Similar Questions

math
two horses gallop off in the sam direction. Trigger travels25 kilometers per hour. Silver travels 30 kilometers per hour. How long before the horses are 3 kilometers apart? 
math
Andrea made a car trip of 440 Kilometers. She averaged 54 Kilometers per hour for the frst part of the trip and 80 kilometers per hour for the secound part. If the total trip took 6 hours, how long was she traveling at 80 kilometers … 
MATH
Andrea made a car trip of 440 Kilometers. She averaged 54 Kilometers per hour for the frst part of the trip and 80 kilometers per hour for the secound part. If the total trip took 6 hours, how long was she traveling at 80 kilometers … 
math
Phil is making a 40kilometer 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 … 
math
Phil is making a 40kilometer 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 … 
math
Phil is making a 40kilometer 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 … 
Math
Two airplanes leave St. Louis at the same time and fly in opposite directions. If one travels at 500 kilometers per hour, and the other at 600 kilometers per hour, how long will it take for them to be 1925 kilometers apart? 
Math
Two airplanes leave St. Louis at the same time and fly in opposite directions. If one travels at 500 kilometers per hour, and the other at 600 kilometers per hour, how long will it take for them to be 1925 kilometers apart? 
Math/Algebra
Delivery company charges $10 plus 40ยข per kilometer or part of a kilometer. Find the cost for a trip of: a.5 kilometers b.7.5 kilometers c.3.2 kilometers d.Graph the ordered pairs (kilometers, cost). Is this a function? 
Math
a woman drives to work and averages 70 kilometers per hour for the trip. On her trip from work to home she averages 100 kilometers per hour. What is her average speed for the round trip?