how many odd and even numbers are there between 42 and 400??
Find the sum of odd numbers and the sum of even numbers!

• the odd numbers are in series 43, 45, ........, 399
  as they r in A.P., 399=43+(n-1)*2
  no. of odd numbers=179
  sum=179*(43+399)/2
  sum of odd numbers = 39559
  Similarly for even numbers, 42, 44, ..........., 400
  no. of even numbers = 180
  sum of even numbers = 39780
• 10 years agoHelpfull: Yes(32) No(4)
• Total no. of numbers b/w 42 & 400=400-42+1=359.As the series is beginning with an even no. & ending with an even no. so number of even nos is more.So, there are (359+1)/2=180 even nos and rest 179 are odd nos.Now using the formula of sum of n terms in an AP[n/2(a+l)] we can can find the sum of the numbers.Sum of even terms is 39780 and that of odd terms is 39559.
• 10 years agoHelpfull: Yes(8) No(3)
• Odd numbers are from 43 to 399.
  Number of odd numbers = l−ad+1=399−(43*2)+1=179
  Their sum = n2(l + a) = 39559
  
  Even numbers are from 44 to 398.
  Number of even numbers = l−ad+1=398−442+1=178
  Their sum = 178^2*(398+44) =39338
  
• 9 years agoHelpfull: Yes(4) No(0)
• sum of odd terms=9559
  sum of even terms=39780
  no of odd terms=79
  no of even terms=180
• 10 years agoHelpfull: Yes(1) No(6)
• sorry no of odd terms is 179
  and sum of odd no is 39559
  
  
• 10 years agoHelpfull: Yes(1) No(0)
• hey i think he askd in between but not including 42 and 400?
  
• 10 years agoHelpfull: Yes(1) No(0)
• Sol: Odd numbers are from 43 to 399. Number of odd numbers = (l−a/d)+1=179
  Their sum = n/2(l+a) = 39559
  
  Even numbers are from 44 to 398. Number of even numbers = (l−a/d)+1=178
  Their sum = 1782(398+44)=39338
  here as the question says that number between 42 to 400 so we should take from 43 to 399 values..
  
• 10 years agoHelpfull: Yes(0) No(0)