﻿ The term digit of 1! + 2! + 3! + … + 49! Is : Kaysons Education

# The Term Digit Of 1! + 2! + 3! + … + 49! Is

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## Question

### Solution

Correct option is

1

We have 1! + 2! + 3! + 4! = 33. Also 5! = 120, 6! = 720, 7! = 5040, 8! = 40320 and 9! = 326880. Thus, the tens digit of

1! + 2! + … + 9! is 1.

Also, note that n! is divisible by 100 for all n ≥ 10, so that tens digit of 10! + 11! + … + 49! is zero. Therefore, tens digit of 1! + 2! + … + 49! is 1.

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