from 21 balls 7 boundaries and 2 sixes
5
There are four sixes and four sevens
7 with 5 remaining 47 - 5 = 42 = 6 x 7
2/3 = 0.66666666... (the sixes continue forever).
Exactly seven of them
Six of them.
yes
1/2
0.04166and infinite sixes so put a line over the first 2 sixes
9 of them with a remainder of 2
No, 2/3 = 4/6