In an ap the 1st term is 25,nth term is -17 and sum to first n terms is 60.Find d
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Given a=25,
tn= -17,
sn=60,
we know that sn= n/2*(a+tn)
tn=a+(n-1)d=-17
60=n/2*(25-17)
60=n/2*(8)
60=4n
n=15
now tn=a+(n-1)d
-17=25+14*d
-42=14d
d=-3
tn= -17,
sn=60,
we know that sn= n/2*(a+tn)
tn=a+(n-1)d=-17
60=n/2*(25-17)
60=n/2*(8)
60=4n
n=15
now tn=a+(n-1)d
-17=25+14*d
-42=14d
d=-3
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