ABC26GN0540 · H.C.F. and L.C.M. of Numbers

Greatest number of 4 digits is 9999. $$\begin{array}{c|rr} 5 & 15-25-40-75 \\ \hline 5 & 3-5-8-15 \\ \hline 3 & 3-1-8-3 \\ \hline & 1-1-8-1 \end{array}$$ L.C.M. of 15, 25, 40 and $75=5 \times 5 \times 3 \times 8=600$. On dividing 9999 by 600, the remainder is 399. $$\therefore \quad \text { Required number }=(9999-399)=9600 .$$