Timmy plans to ride a skateboard ramp that is 50 feet high. He knows he needs to go 40 mph at the start to make it all the way to the top. He measures his speed on three trial runs and goes 36, 34, and 38 mph. How much faster does he have to go than his average speed to make it up the ramp?
His total speed from the trials is 108 because 36 + 34 + 38 = <<36+34+38=108>>108
His average speed was 36 mph because 108 / 3 = <<108/3=36>>36
He needs to go 4 mph faster to make it to the top because 40 - 36 = <<40-36=4>>4.
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