A positive number when decreased by 2 is equal to 15 times the reciprocal of the number. What is the number ?

One Answer on this Question

1. Let the number be x.

   So x-2 =15/x, or

   x^2–2x-15=0, or

   (x-5)(x+3)=0

   Hence x = 5 or -3.

   Check: When x=5, 5–2=3 which is 15/5=3.

   When x=-3, -3–2=-5 which is 15/-3=-5.

   The number is 5 or -3.

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