31/98
42/490 in simplest form is 3/35.
2/5
490 cannot be simplified further.
0.0857
4/90 = 2/45
250 over 490 in lowest terms is 25/49
490/756 = 35/54
XD is not in the standard form for a Roman numeral, but I would guess its value is 490. It should be written as CDXC
It is: 2^1 times 5^1 times 7^2 = 490
7
3/7
490 = 490