### SAT help - how to deal with 'average'

A http://www.door2math.com production. Dr. Pan makes learning math Fun. SAT Math question, What is the difference between the greatest and least possible values of t if..? Twenty students averaged t on a test. Test scores ranged from 0 to 100 inclusive. The average score for the first 15 papers graded was 70. What is the difference between the greatest and least possible values of t?

Length:
03:51