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put this solution on YOUR website!Since the "average speed, s, was between 90 and 120 mph.", this means that the average speed was faster than (or the same speed as) 90 mph AND was slower than (or the same speed as) 120 mph.
Mathematically, this means that the average speed "s" is both greater than or equal to 90 mph AND less than or equal to 120 mph
So the inequality is