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प्रश्न
Insert 7 A.M.s between 2 and 17.
उत्तर
Let \[A_1 , A_2 , A_3 , A_4 , A_5 , A_6 , A_7\] be the seven A.M.s between 2 and 17.
Then, 2, \[A_1 , A_2 , A_3 , A_4 , A_5 , A_6 , A_7\] and 17 are in A.P. whose common difference is as follows:
d = \[\frac{17 - 2}{7 + 1}\] = \[\frac{15}{8}\]
\[A_1 = 2 + d = 2 + \frac{15}{8} = \frac{31}{8}\]
\[ A_2 = 2 + 2d = 2 + \frac{15}{4} = \frac{23}{4}\]
\[ A_3 = 2 + 3d = 2 + \frac{45}{8} = \frac{61}{8}\]
\[ A_4 = 2 + 4d = 2 + \frac{15}{2} = \frac{19}{2}\]
\[ A_5 = 2 + 5d = 2 + \frac{75}{8} = \frac{91}{8}\]
\[ A_6 = 2 + 6d = 2 + \frac{45}{4} = \frac{53}{4}\]
\[ A_7 = 2 + 7d = 2 + \frac{105}{8} = \frac{121}{8}\]
Hence, the required A.M.s are
\[\frac{31}{8}, \frac{23}{4}, \frac{61}{8}, \frac{19}{2}, \frac{91}{8}, \frac{53}{4}, \frac{121}{8}\].
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