Question

The natural numbers are divided into groups as (1), (2,3), (4,5,6), (7,8,9,10) and so on. The sum of numbers in the 50th group is
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Answer 1

Answer:

Description for Correct answer:

Let S =1+2+4+7+...+Tn

or S = 1+2+4+...+Tn−1+Tn

Subtracting, we get

O = 1+[1+2+3+...(n-1)]-Tn

=> Tn = 1+2+3+.....+(n-1)+1

= n(n−1)2+1

∴First number of 50th term

= 50×492+1= 1226

∴Sum of numbers of 50th term

= 1226 + 1227 + ......upto 50th

term =502[2×1226+(50−1)×1

Answer 2

Answer:

31875 I think it is correct