The unit digit of the sum of factorials from 1! to n! is always 3 if n = 5. This is because the unit digit of the factorial of any number greater than 4 is always 0.

Here's why:

1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
...

As you can see, starting from 5!, the unit digit is always 0.

So, if we add up the unit digits of the factorials from 1! to n! where n = 5, we get 1 + 2 + 6 + 4 = 13. The unit digit of 13 is 3.

Therefore, the unit digit of 1! + 2! + 3! + 4! + 5! +....+ 768! is 3.

Question

The unit digit of the sum of factorials from 1! to n! is always 3 if n >= 5. This is because the unit digit of the factorial of any number greater than 4 is always 0.

Here's why:

1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
...

As you can see, starting from 5!, the unit digit is always 0.

So, if we add up the unit digits of the factorials from 1! to n! where n >= 5, we get 1 + 2 + 6 + 4 = 13. The unit digit of 13 is 3.

Therefore, the unit digit of 1! + 2! + 3! + 4! + 5! +....+ 768! is 3.

Knowee AI · Accepted Answer

The unit digit of the sum of factorials from 1! to n! is always 3 if n >= 5. This is because the unit digit of the factorial of any number greater than 4 is always 0.

Here's why:

1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
...

As you can see, starting from 5!, the unit digit is always 0.

So, if we add up the unit digits of the factorials from 1! to n! where n >= 5, we get 1 + 2 + 6 + 4 = 13. The unit digit of 13 is 3.

Therefore, the unit digit of 1! + 2! + 3! + 4! + 5! +....+ 768! is 3.

Find the unit digit of 1! + 2! + 3! + 4! + 5! +....+ 768! ?Options1934

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