The answer is 75mph.
Solution:
Convert Feet per Second to mph | Study.com via kwout
2464ft / 22.4sec x 1mi / 5280ft x 60sec / 1min x 60min / 1hr = 8,870,400/11,8272 = 75mph
Where:
1mi = 5280ft
1min = 60sec
1hr = 60 min
In 1959 the international yard and pound agreement (between the United States and countries of the Commonwealth of Nations) defined a yard as being exactly 0.9144 metres, which in turn defined the foot as being exactly 0.3048 metres (304.8 mm).
mi = ft * 0.00018939
Miles is a unit of length equal to 1760 yards.
You can use this Feet per second to Miles per hour (ft/s to mph) conversion calculator for Speed conversions with additional tables and formulas.