Discussion :: Numbers
-
(51 + 52 + 53 + ... + 100) = ?
Whatsapp
Facebook
Answer : Option D
Explanation :
Sn = (1 + 2 + 3 + ... + 50 + 51 + 52 + ... + 100) - (1 + 2 + 3 + ... + 50)
=\( \frac { 100 } { 2 } \)x (1 + 100)-\(\frac {50 } { 2 }* \) (1 + 50)
= (50 x 101) - (25 x 51)
= (5050 - 1275)
= 3775.
Be The First To Comment