permutation combination

The unit's digit of 1! +2! +3!+.....+97! is

a)3
b)4
c)5
d)6

explain yur answer with steps...

2 Answers

1!=1
2!=2
3!=6
4!=24
5!=120

after this rest will have zero in unit plzce....so add the nos..u get :3

arey,its that easy!!!!!!!!!!!!!!!! didnt know that much also..

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