Exactly 9 times
68 goes 9 times in 621.52, leaving 9.52 (621.52-9x68).
68 times with a remainder of 4
615 ÷ 9 = 68 with remainder 3
9 times with a remainder of 5
6 with remainder 9.
7 x 9 = 63, so, 9 times with a remainder of 5.
7 times with a remainder of 5
68 = 7b - 9 -7b = -68-9 b = (-68-9)/-7 = 11
7 times with a remainder of 5
9 times
7 with remainder 5.