Question

The remainder obtained,when 1!+2!+3+...+175! Is divided by 15 is

Answer 1

Nice Question (But easy one)

Question :--- we have to find the remainder when 1!+2!+3+...+175! Is divided by 15 ?

solution :--- we know that, a number is divisible by 15 when it is divisible by 3 and 5 both.

so, After 5! or starting from 5! every digit have 3 and 5 , so we just have to look before 5!

(That was the main logic)

we know ,

1! = 1

2! = 2

3! = 6

4! = 24

so,

1! + 2! + 3! + 4! = 33

and after this all digits are already divisible by 15.

so, our remainder will be = $\huge{\frac{3</strong><strong>3</strong><strong>}{</strong><strong>1</strong><strong>5</strong><strong>}}$

===== $\large\red{\boxed{\sf </strong><strong>3</strong><strong>\</strong><strong>:</strong><strong>(</strong><strong>Ans</strong><strong>)</strong><strong>}}$

$\huge\underline\mathfrak\green{Hope\:it\:Helps\:You}$

(Mark as brainlist ❤️)