SOLUTION: A homing device left its home to deliver a mesage. on takeoff, the device encountered a tailwind of 15 mph and made the delivery in 5 minutes. The return trip into the wind took 10

Algebra.Com
Question 219289: A homing device left its home to deliver a mesage. on takeoff, the device encountered a tailwind of 15 mph and made the delivery in 5 minutes. The return trip into the wind took 10 minutes. How fast does the device fly in still air?

llaws@mrhs.com

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
A homing device left its home to deliver a mesage. on takeoff, the device encountered a tailwind of 15 mph and made the delivery in 5 minutes. The return trip into the wind took 10 minutes. How fast does the device fly in still air?
----------
Let x be the rate of the device in still air.
------------------
Downwind DATA:
time = 1/12 hr ; rate = x+15 mph ; distance = rt = (1/12)(x+15) miles
-------------------------
Upwind DATA:
time = 1/6 hr ; rate = x-15 mph ; distance = rt = (1/6)(x-15) miles
-------------------------
Equation:
distance = distance
(1/12)(x+15) = (1/6)(x-15)
Multiply both sides by 12 to get:
x+15 = 2x-30
x = 45 mph (speed of the device in still air)
==================================================
Cheers,
Stan H.

RELATED QUESTIONS

A homing device left its home to deliver a message. On takeoff the device encountered a... (answered by ankor@dixie-net.com)
The following circuit operates if and only if there is a path of functional devices from... (answered by ikleyn)
Hi, I am really struglling with this question. It's a little tricky. Any help will be... (answered by stanbon)
fred is analyzing the cost of producing two different items at an electronics company. an (answered by stanbon)
PLEASE HELP AND EXPLAIN A mechanical device requires 420 J of work to do 230 J of work (answered by MathLover1)
telephone answering devices. Seventy-seven percent of U>S> homes have a telephone... (answered by stanbon)
The volume V of a given mass of gas varies directly as the temperature T and inversely as (answered by Cromlix,Edwin McCravy)
The volume V of a given mass of gas varies directly as the temperature T and inversely as (answered by ikleyn)
an electronic device is made up of two components A and B such that the device would work (answered by ikleyn)