1680 and its multiples.
840, 1680, 2520 and so on.
840, 1680, 2520
1680 divided by 4 is equivalent to 420.
420, 840, 1260, 1680, 2100, 2520, 2940 +420 . . .
336, 672, 1008, 1344, 1680
There are not just three common multiples, but infinitely many. They are 168 and it multiples, so 1680 and 16800.
280 560 840 1120 1400 1680 1960 2240 2520 2800
The total number of multiples is infinite. Here are the first 10: 420, 840, 1260, 1680, 2100, 2520, 2940, 3360, 3780, 4200 . . .
420, 840, 1260, 1680, 2100, 2520, 2940, 3360, 3780.
1680 to get this answer you need to get the factorial of 8 and the factorial of 4! like so 8! is n! 8*7*6*5*4*3*2*1=n!_40320 4! is r! 4*3*2*1=r!_24 now divide the two! n!/r!(n-r)!=1680 8!/4!(8-4)!=1680 8!/4!=1680
All multiples MUST be multiples of 4.