A child was asked to add first few natural numbers(that is 1+2+3+4+5....)so long as his patience permitted . as he stopped he gave the sum as 575. when the teacher declred the result wrong , the child discovered he had missed one number in the sequence during addition . the no. he missed was?

• Number missed=20
  checking for first n natural number sum=n*(n+1)/2
  for n=34, sum=34*35/2= 595
  So the number missed= 595- 575 =20
• 11 years agoHelpfull: Yes(1) No(0)