Sarah asked in Science & MathematicsMathematics · 2 weeks ago

# A plane flies at 160 mph for the first and last half hour of a flight. It flies at a higher constant speed for the rest of the flight....?

A plane flies at 160 mph for the first and last half hour of a flight. It flies at a higher constant speed for the rest of the flight. The route is 2040 miles. The plane is 940 miles from the destination 2 hours before the end of the flight.

How many hours is the entire flight?

Relevance
• RR
Lv 7
2 weeks ago

0.5 hours from the end of the flight, it is 160/2 = 80 miles from at the destination.

In the 1.5 hours before the end of the flight, it travels

940- 80 = 860 miles.

Speed for this section is 860/1.5 = 573.3 mph

The total flight is

1 hour @ 160 mph travelling 160 miles

t hours @ 573.3 mph travelling 2040-160 = 1880 miles

Total time = 1880/573.3 = 3.28 hours

total time = 3.28 + 1.0

= 4.28 hours

= 4hours 17 minutes

• alex
Lv 7
2 weeks ago

higher constant speed = (940-80)/1.5 = 573 1/3 mph

time = 1 +(2040-160-940)/(573 1/3) + 2 = 4.64 hours=4 hr 38min