The second question and the first question have something in common and are also decomposed. The second question requires the same divisor, according to; Dividend = quotient × divisor+remainder

200= 196 + 4 = 2 × 98 + 4

300=294 + 6 = 3 × 98 + 6

500=490 + 10 = 5 × 98 + 10

Quotient 2, 3 and 5 are pairwise coprime, so the maximum number is 98.