CBSE Class 10 Answered
How many terms of an AP 9,17,25.... must be taken to give a sum of 636?
Asked by sumitkain2016 | 24 Feb, 2019, 08:05: PM
Expert Answer
First term of A.P. = 9 , common difference = 8
if sum of n terms 636, Sn = (n/2) [ 2×9 + (n-1)8 ] = 636
Sn = n [ 10+ 8n] = 1272
8n2 +10n -1272 = 0
4n2 +5n -636 = 0
By factorising LHS, (4n+53)(n-12) = 0
hence n = 12
Answered by Thiyagarajan K | 24 Feb, 2019, 08:25: PM
Application Videos
Concept Videos
CBSE 10 - Maths
Asked by pathakvaishnavi9139 | 23 Mar, 2024, 10:45: AM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by mustafahssn786 | 23 Mar, 2024, 06:25: AM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by choudharyniki001 | 22 Mar, 2024, 08:49: AM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by jagdishdabang79 | 18 Mar, 2024, 08:40: PM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by vn3950372 | 18 Mar, 2024, 08:38: PM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by vestigevestige85 | 17 Mar, 2024, 09:44: PM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by jayashreelatha04 | 17 Mar, 2024, 05:38: PM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by suvarnaapkare | 15 Mar, 2024, 04:59: PM
ANSWERED BY EXPERT
CBSE 10 - Maths
Asked by anubhutiupadhaya | 15 Mar, 2024, 03:33: PM
ANSWERED BY EXPERT