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NDA 2013
Exam
NDA
Year
2013
Subject
Mathematics
Chapter
Sequences and Series

NDA 2013 · Mathematics · Sequences and Series

If the positive integers a, b, c, d are in AP, then the numbers a b...

If the positive integers a,b,c,da, b, c, d are in AP, then the numbers abc,abd,acd,bcda b c, a b d, a c d, b c d are in

Options

  1. AHP
  2. BAP
  3. CGP
  4. DNone of the above

Correct answer

A. HP

Step-by-step solution

a,b,c,da, b, c, d are in A.P. then, 1a,1b,1c,1d\frac{1}{a}, \frac{1}{b}, \frac{1}{c}, \frac{1}{d} are in H.P. or, abcda,abcdb,abcdc,abcdd\frac{a b c d}{a}, \frac{a b c d}{b}, \frac{a b c d}{c}, \frac{a b c d}{d} are in H.P. or, bcd,acd,abd,abcb c d, a c d, a b d, a b c are in H.P.
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