Three times a number subtracted from a product of 15 & the reciprocal of a number

Answer 1

15(1/x) - 3x where x = the number. 3 times a number = 3x, and product of 15 and the reciprocal or inverse of the number = 15(1/x) = 15/x

=15/x -3x you might stop here, but it's also equivalent to some more

= 15/x -3x^2/x

= (15-3x^2)/x

about all you can do, unless there's some more information in the problem that somehow got left out?