Question

Find the remainder when 1!+2!+3!......+100! is divided by 12

Answer 1

1!=1

2!=1*2

3!=1*2*3

4!=1*2*3*4 =>2*12

so 5!=(2*12)*5

hence all the factorials greater than 3 will be a multiple of 12.

so the lengthier problem can be simplified as

(1!+2!+3!) /12=> 9/12 => remainder 9.

If it is correct pls make me as brainlist