The top students' math problems are divided by 643+ 13, 1 140+6 and 1244. What is the maximum divisor?
∫ A number divided by 643 is 13, divided by 1 140 is 6, and divided by 1244 is 16643- 13 = 630. 1244+16 =1260 ∴ A common divisor whose number is 630, 1 134,1260 630 = 2 * 3 * 5 *. ...