The desired number will be one less than the least common multiple of 10, 9, 8, 7. A = 5*9*8*7 - 1 = 2519.
Check 2519/10 = 251 r 9 2519/9 = 279 r 8 2519/8 = 314 r 7 2519/7 = 359 r 6 Note we also have ... 2519/6 = 419 r 5 2519/5 = 503 r 4 2519/4 = 629 r 3 2519/3 = 839 r 2 2519/2 = 1259 r 1
Check 2519/10 = 251 r 9 2519/9 = 279 r 8 2519/8 = 314 r 7 2519/7 = 359 r 6 Note we also have ... 2519/6 = 419 r 5 2519/5 = 503 r 4 2519/4 = 629 r 3 2519/3 = 839 r 2 2519/2 = 1259 r 1