the sum pf 30 terms in AP ,whose last term is 98, is 1635. Find the first term and common difference.
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S30=1635
l=98
S30=n/2 (a+l)
1635=15 (a+98)
1620-98= a
1522=a
l= a+(n-1)d
98=1522+(29)d
98-1522=29d
-1424=29d
d=-49.1
Answered by
3
answer is.........
given n=30
last term (l)=98
Sn=1635
we know that ,
Sn=n/2(a+l)
1635=30/2(a+98)
1635=15(a+98)
327=3(a+98)
109=a+98
11=a
given last term =98
an=a+(n-1)d
98=11+(29)d
87=29d
3=d
I HOPE THIS WILL HELP U
given n=30
last term (l)=98
Sn=1635
we know that ,
Sn=n/2(a+l)
1635=30/2(a+98)
1635=15(a+98)
327=3(a+98)
109=a+98
11=a
given last term =98
an=a+(n-1)d
98=11+(29)d
87=29d
3=d
I HOPE THIS WILL HELP U
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