in an ap if a=12 an=248 sn=7800 find n and d
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Answer:
n=60
d= 4
Step-by-step explanation:
Sn= n/2(a+an)
7800=n/2(12+248)
7800 x 2/260=n
60=n
an= a+ (n-1)d
248= 12 + 59d
248-12=59d
236/59=d
4=d
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