An example for #1 would be that: 15 is divisible by 3, but not 9. every third multiple of 3, (9, 18, 27,...) is divisible by 9 because 9 is three times the size of 3.
For part two the first number that I thought of is 23.
You have a grade percentage of 85% in the class after the 50 points are added.
(4^9)^5 * 4^0
4^45 * 1
4^45 in its simplest form (in other words, a very large number).
1.23794004E+27
