A professor has recorded exam grades for 40 students in his class, but one of the grades is no longer readable. If the mean score on the exam was 82 and the mean of the 39 readable scores is 84, what is the value of the unreadable score?

3 1/4 lbs1 lb = 16 oz3 1/4 * 16 = 13/4 * 16 = 52 oz <==

0.15 gal every secondfor 20 seconds = 0.15(20) = 3 gal per 20 seconds.
if there is 2 pints in a qt, and 4 qts in a gal...then there is 8 pints in a gal.
3 gal = (8 * 3) = 24 pints dispensed in 20 sec