Let x, y, and z be the three quotients of the divisions; the number sought will then be expressed by 28 x + 10, by 19 y + 2, or by 15 z + 4. Hence the two equations

28 x + 10 = 19 y + 2 = 15 z + 4.

To solve the equations 28 x + 10 = 19 y + 2, or y = x + 9 x + 8

19
, let m = 9 x + 8

19
, we have then x = 2 m + m - 8

9
.
Let m - 8

9
= m′; then m = 9 m′ + 8; hence

x = 18 m′ + 16 + m′ = 19 m′ + 16 . . . (1).

Again, since 28 x + 10 = 15 z + 4, we have

15 z = 28 x + 6, or z = 2 x - 2 x - 6

15
.
Let 2 x - 6

15
= n; then 2 x = 15 n + 6, and x = 7 n + 3 + n

2
.
Let n

2
= n′; then n = 2 n′; consequently

x = 14 n′ + 3 + n′ = 15 n′ + 3 . . . (2).