Question

5. The sum of the first 20 positive integers will be :
(A) 180
(B) 190
(C) 200
(D) 210
Ans. (D) 210​

Answer 1

.........

........

D. 210

Answer 2

Answer:

Sum of first n positive integer is

n(n+1)

-----------

2

So for n = 20

(20× 21)

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2

10 × 21 = 210

option (D) is correct