Well, since the numbers are consecutive and their product is 210, both of them must be pretty close to the square root of 210.
The square root of 210 is  14,491...
so why don't we take a look at 14 and 15 and see what we get.
(14) x (15) = 210 !
Well whaddaya know !  The numbers on the tickets are  14  and  15 .
#14 is now being served, and #15 should be getting ready.