Question

how many consecutive natural numbers starting from 1 should be added to get 78?​

Answer 1

Answer:

12

Step-by-step explanation:

n(n+1)/2 =78

n^2+n=156

n^2+n-156=0

(n+13)(n-12)=0

so n can be -13 and 12 but as n is positive only so the answer is 12