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p , q , r and s are in AP such that p + s =8 and qr =15 . What is the difference between largest and smallest numbers?

Options

  1. A6
  2. B5
  3. C4
  4. D3

Correct answer

A. 6

Step-by-step solution

p, q, r, s in AP p+s=8 q+r=8 and q r=15 By observation, q and r can take values 3 or 5 . The possible AP can be 1,3,5,7 or 7,5,3,1 . Difference =7-1=6 .

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