5. Three military trains passed through the railway station. The first had 462 soldiers, the second had 546, and the third had 630. How many cars were in each train if it is known that each car had the same number of soldiers and that this number was the largest possible?
5. The number of soldiers traveling in each carriage is the greatest common divisor of the numbers 462, 546, and 630. GCD $(462,546,630)=42$. Therefore, in the first train there were 11 carriages $(462: 42=11)$, in the second $13(546: 42=13)$, in the third $-15(630: 42=15)$.