Question

sum of first 80 natural number​

Answer 1

ƭσ ƒเɳ∂ 

Sum of first 80 natural numbers.

รσℓµƭเσɳ

The AP sequence will be.

1 , 2 , 3 , 4 ,.............., 80

From this sequence we got the required values as.

a = 1

d = 1

l = 80

n = 80

ƒσɾɱµℓα µรε∂

Sn = n/2 [ a+l]

cαℓcµℓαƭเσɳ

>> S80 = 80/2[1+80]

>> S80 = 40(81)

>> S80 = 3240.

So sum of first 80 natural numbers will be

3,240