SOLUTION: Supposed flying in a calm air a robin can reach a speed of 25 kilometers per hour. Each day, this robin flies from its nest to the nearest body of water 1 kilometer away. On one pa

Question 1138663: Supposed flying in a calm air a robin can reach a speed of 25 kilometers per hour. Each day, this robin flies from its nest to the nearest body of water 1 kilometer away. On one particular day it flew into a headwind and on its return trip the wind was at it's back. if the total trip took 1/10 of an hour, what was the speed of the wind?
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
Supposed flying in a calm air a robin can reach a speed of 25 kilometers per hour.
Each day, this robin flies from its nest to the nearest body of water 1 kilometer away.
On one particular day it flew into a headwind and on its return trip the wind was at it's back.
if the total trip took 1/10 of an hour, what was the speed of the wind?
:
let w = the speed of the wind
then
(25-w) = the ground speed against the wind
and
(25+w) = the speed with
:
Write a time equation; time = dist/speed
to lake time + return time = .1 hr
+ = .1
multiply equation by (25-w)(25+w), cancel the denominators
(25+w) + (25-w) = .1(25-w)(25+w)
25 + 25 + w - w = .1(-w^2 + 625); difference of squares
50 = -.1w^2 + 62.5
.1w^2 = 62.5 - 50
.1w^2 = 12.5
multiply both sides by 10
w^2 = 125
w =
w = 11.18 km/hr is the speed of the wind
:
:
Check this, find the actual time each way
= .0724 hrs
= .0276 hrs
------------------------------
round trip time: = .1000 hrs

RELATED QUESTIONS
A plane took 1 hour and 20 minutes to go 600 miles when flying with the jet stream and 2 (answered by checkley75)

If a plane flies 200 mph in calm air and the rate of the wind is r miles per hour, then... (answered by Alan3354)

A plane flies at x miles per hour in still air. Flying with a tailwind, its speed is... (answered by dfrazzetto)

An air force plane flies at a speed that is 30 kilometers per hour faster than a cargo... (answered by VFBundy,MathTherapy)

1- a six passanger plane cruises at 180 mph in calm air. If the plane flies 7 miles with... (answered by Nate,ankor@dixie-net.com)

A plane flies 460 mph in calm air. Flying with the wind, the plane can travel 1560 miles... (answered by macston)

A plane is is flying at a speed of 6,000 meters per minute. what is this speed in... (answered by mananth)

Flying with the wind, a plane can travel 1100 miles in 4 hours. Against the wind, the... (answered by ikleyn)

Can anyone help? I need to solve this problem with work shown: Show a complete... (answered by stanbon)