Question

What is the sum of first 10 natural numbers ? give a formula for that !!

Answer 1

The formula for finding the sum of any first 'n' numbers is -
n(n+1)/2 

Put 10 in the equation,
= 10(10+1)/2 
= 110/2
= 55

Answer 2

sum of first 10 nos.
=1+2+3+4+5+6+7+8+9+10
=55

the formula for that is 
n(n+1)/2