Police can estimate the speed of a vehicle before the brakes are applied using the formula 0.75d = s^2 / 30.25 where is the speed in miles per hour d is the length of the vehicle's skid marks. what was the approximate speed of a vehicle that left a skid mark measuring 160 feet? 1.about 36 miles per hour 2."" 60 "" 3."" 13 "" 4"" 54 ""

So we have the formula to calculate the speed of a vehicle before the breaks were applied using the measure of it's skid marks:
We also know from our problem that the vehicle left a skid mark measuring 160 feet, so . Lets replace that value in our formula to find the speed :







We can conclude that the speed of the car before the brakes were applied was about 60 miles per hour.