The average speed, s, was between 110 and 120 mph.

Question

translate to a inequality

Answer 1

If Kay's age, A, is between 16 and 20, we write:
16<A<20.
How would you attempt the question about average speed?

Answer 2

110<A<120

Answer 3

Almost...
"the average speed, s, was..."
so you need to put the variable as "s",
110 < s < 120