Question 586130
Let assume first number is xy ie.  10x+y

second number is 10y+x,   

third number is 100x+ y


Difference between first and second = distance between second and third.


=> 10y +x -(10x+y) = 100x+y - (10y+x)


after solving this we get,  y = 6x


so, only possible value of x is 1, otherwise y will become two digit number.


so, numbers are 16, 61 and 106. 


speed = 61-16 = 45 miles per hour.


if any doubt, feel free to ask....