Answers

  • qais
  • Content Quality
2016-03-19T20:41:53+05:30
Let the first term be a
common difference is d
4th term= a +(4-1)d = a+3d
2nd term= a + (2-1)d = a+d
9th term = a +(9-1)d = a +8d
6th term= a+(6-1)d = a+5d
A/q,
a+3d =2(a+d) = 2a +2d
⇒a -d =0
⇒a=d
also,
a+8d = (a+5d)+7
⇒a+8d = a+5d+7
⇒3d=7
⇒d =7/3
so,a =7/3
now. 15th term = a +(15-1)d = (7/3) + 14×(7/3) = (7/3)×15 = 35
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