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There are four numbers of which the first three are in G.P. and the last three are in A.P., whose common difference is 6 . If the first and the last numbers are equal then two other numbers are

Options

  1. A-2,4
  2. B-4,2
  3. C2,6
  4. Dnone

Correct answer

B. -4,2

Step-by-step solution

Let the last three numbers in A.P. be a, a +6 , a +12, then the first term is alsoa +12 . But a+12, a, a+6 are in G.P. a ²=( a +12)( a +6) a ²= a ²+18 a +72 a =-4 The numbers are 8,-4,2,8.

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