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Let A1, A2, A3,…. be an increasing geometric progression of positive real numbers. If A1A3A5A7 = 1 1 2 9 6  and A2 + A4 = 7 3 6 ,  then, the value of A6 + A8 + A10 is equal to

Option 1 -

33

Option 2 -

37

Option 3 -

43

Option 4 -

47

0 3 Views | Posted 2 months ago
Asked by Shiksha User

  • 1 Answer

  • P

    Answered by

    Payal Gupta | Contributor-Level 10

    2 months ago
    Correct Option - 3


    Detailed Solution:

    Let   A 2 A 1 = A 3 A 2 = . . . = r

    ∴ A 1 A 3 A 5 A 7 = 1 1 2 9 6              

    ⇒ A 1 r 3 = 1 6 . . . . . . . ( i )               

    Again, A2 + A4 = 736

    A1r=736−16=136........(ii)

    (i)&(ii)r=6&A1=1366

    ∴A6+A8+A10=A1r5(1+r2+r4)=43             

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