if a=6,an=101,sn=1190. find n and d
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a = 6 , an = 101 , Sn = 1190
an = a+(n-1)d
101 = 6+(n-1)d
101-6 = (n-1)d
95. = (n-1)d
Sn = n/2 [a+an]
1190=n/2[6+101]
1190×2 = n [107]
2380 = n×107
2380 = 107n
2380/107 = n
22.2= n
Therefore
95=(22.2-1)d
95=11.2d
95/11.2=d
8.5 =d
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