A helicopter flies 312 miles against the wind in 2 hours; with the wind, it can fly 468 miles in the same amount of time. Find the speed of the helicopter in still air.

Step-by-step explanation:

If a helicopter flies 312 miles against the wind in 2 hours, the speed of the helicopter in air is expressed as shown;

Speed = Distance/Time

Speed = 312miles/2hours

Speed = 156miles/hr

The speed of the helicopter against the wind is 156miles/hr

If it can fly 468 miles in the same amount of time, the speed during this time at this distance will be;

speed = 468 miles/2hours

Speed = 234miles/hr

The speed of the helicopter in still air = Speed while flying - Speed while against the wind

The speed of the helicopter in still air = 234miles/hr - 156miles/hr

The speed of the helicopter in still air  = 78miles/hour

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step-by-step explanation: