Data set E consists of 20 integers with frequencies in intervals as follows:
4 in $[10,20)$, 5 in $[20,30)$, 6 in $[30,40)$, and 5 in $[40,50)$.

Data set F has the same shape but all intervals are shifted 10 units higher:
4 in $[20,30)$, 5 in $[30,40)$, 6 in $[40,50)$, and 5 in $[50,60)$.

What is the difference between the mean of F and the mean of E?