SOLUTION: I desparately need help on this word problem! I am able to get part a, but b and c are giving me trouble. A rescue helicopter is flying an aircraft carrier 350 miles to Pearl Harb

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Question 579493: I desparately need help on this word problem! I am able to get part a, but b and c are giving me trouble.
A rescue helicopter is flying an aircraft carrier 350 miles to Pearl Harbor. The point of no return is the point where it would take as much time to fly back to aircraft carries as it would to fly on to Pearl Harbor. The airspeed of the helicopter is 175mph & it's flying with a 25mph tailwind. A. Calculate the total time for the helicopter to fly to Pearl Harbor. B. once the helicopter is at the point of no return, determine the time it will take to complete the trip.
C. Use the results from parts A & B to determine the time for the helicopter to reach the point of no return. Thanking in advance for your help!!
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A rescue helicopter is flying from an aircraft carrier 350 miles to Pearl Harbor.
The point of no return is the point where it would take as much time to fly back to aircraft carries as it would to fly on to Pearl Harbor.
The airspeed of the helicopter is 175mph & it's flying with a 25mph tailwind.
:
A. Calculate the total time for the helicopter to fly to Pearl Harbor.
Time = dist/speed
:
t = 350%2F%28%28175%2B25%29%29
t = 1.75 hrs
:
B. once the helicopter is at the point of no return, determine the time it will take to complete the trip.
:
effective speed with the wind = 175+25 = 200 mph
effective speed against the wind = 175-25 = 150 mph
;
Point of no return is when the travel time there and return is the same
;
Write time equation; time = dist/speed:
let p = point of no return from the carrier
then
(350-p) = point of no return from Pearl
:
Write a time equation; time = dist/speed
:
time to return to carrier = time to continue to Pearl
p%2F150 = %28%28350-p%29%29%2F200
cross multiply
200p = 150(350-p)
200p = 52500 - 150p
200p + 150p = 52500
350p = 52500
p = 52500%2F350
p = 150 mi from the carrier
Find the time to return
150%2F150 = 1 hr to return to the carrier against the wind
Find the time to continue
%28%28350-150%29%29%2F200 = 1 hr to complete the trip (with the wind)
:
:
C. Use the results from parts A & B to determine the time for the helicopter to reach the point of no return.
Point of no return is 150 mi from the carrier, it's speed is 200 mph, therefore:
150%2F200 = .75 hrs or 45 min