Bobby. If you find the common denominator here which is 12 then Mina has 4/12 red pencils, bobby has 8/12 red pencils, and julia has 6/12 repent ils. Therefore bobby has the most red pencils.
The answer is 1680. To get this you do 8*7*6*5 because there are 8 options for the first character, and then you can repeat that for the second one with 7, 6, and 5
Simply divide 650/676=.9615 or 96.15%. So there was 3.85% error