-28 and 15
55
23
936. All numbers divisible by 12 and 13 are multiplies of the lowest common multiple of 12 and 13 which is 156. 999 ÷ 156 = 621/52 ⇒ greatest multiple of 156 not bigger than 999 is 6 x 156 = 936.
141
0
13
-35
49
4 and 9
-113
-28 and 15
55
23
55
-27
936. All numbers divisible by 12 and 13 are multiplies of the lowest common multiple of 12 and 13 which is 156. 999 ÷ 156 = 621/52 ⇒ greatest multiple of 156 not bigger than 999 is 6 x 156 = 936.