Question

how many consecutive odd number must ne add to get 400​

Answer 1

Answer:

20.

Step-by-step explanation:

Sn = (n/2)(a1+a1+d(n-1))

Where, S = sum, a1 = first term,

n = number of terms

d = common difference

=> 400 = (n/2) (1+1+2(n-1))

=> 400 = (n/2) (2+2n-2)

=> 400 = (n/2) (2n)

=> 400 = n²

=> √400 = n

=> √20² = n

=> n = 20

Hope it helps you....