For an A.P the first and the last term are 13 and 216 respectively.Common difference is 7. How many terms are there in the A.P.? Find the Sum of all terms.
Answers
Answered by
2
Step-by-step explanation:
nth term = a+ (n-1)d
216 = 13 +(n-1)7
203 = 7n - 7
n = 30
There are 30 terms in this A.P
Sum of n terms = n/2 × (a+l)
=30/2 × (13 + 216)
= 15 × 229
= 3435
HOPE THIS HELPS YOU
Answered by
2
Step-by-step explanation:
Last term = a+(n-1)d
a=first term
n=no of term
d=common difference
Last term = 216
216=a+(n-1)d
216=13+(n-1)7
216-13=(n-1)7
203=(n-1)7
203/7=(n-1)
29=(n-1)
n=29+1
n=30
Sum of n term = n/2(a+l)
Sn=30/2(13+216)
=15(229)
=3435
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