(Q). Find first non-zero digit (FNZD) in 20! + 30! + 40! + 50! + 60!.
Solution:-
Hence FNZD of the least factorial number i.e. 20!, will also be the FNZD of the summation.
∴ FNZD(20!) =
= 2⁴ × 4!
= 16 × 24
= 04 Answer
(Q). Find first non-zero digit (FNZD) in 20! + 30! + 40! + 50! + 60!.
Solution:-
Hence FNZD of the least factorial number i.e. 20!, will also be the FNZD of the summation.
∴ FNZD(20!) =
= 2⁴ × 4!
= 16 × 24
= 04 Answer