book Maths Puzzle Numerical Ability

This question is from Chemistry class "Chemical Equilibrium" -I just cannot figure it out, I've been trying for the last 3 hours to solve it. I will give you the answere as copied

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A TORTOISE AND A HAIR LEAVE THE SAME PLACE AT THE SAME TIME. THE HAIR TRAVELS AT 30M/HR. AFTER 30 MIN THE HAIR HAS WENT 14.915 MILES FARTHER THAN THE TORTOISE. WHAT SPEED IS THE TORTOISE TRAVELING? Seven more than the sum of the largest and smalledst of three consecutive even integers is one less than three times the middle number. Find the middle number. How do i do this?