The Speed of Light is 3 × 10⁸ Meters per Second
It means In one second Light travels a Distance of 3 × 10⁸ Meters
We know that One Hour is made up of 60 minutes and Each Minute has 60 seconds.
One Hour has 60 × 60 = 3600 seconds
In 3600 seconds Light Travels a Distance of 3 × 10⁸ × 3600 Meters
In One hour Light Travels a Distance of 3 × 10⁸ × 3600 Meters
We know that One Mile = 1610 Meter
3 × 10⁸ × 3600 Meters in Miles = (3 × 10⁸ × 3600)/1610 = 6.7 × 10⁸ Miles
The Speed of Light in Miles per Hour is 6.7 × 10⁸