What number produces a rational number when added to 0.5

0.5 is a rational number. To keep the sum rational, the addend must also be rational. The square root of a number which is not itself a perfect square is irrational, so A cannot be the answer, because the sum would be irrational. B is a rational number and therefore when added to 0.5 produces another rational number, 0.75.

-3 bc it is a rational number and when you add -3.5 + 0.5 = -3.0

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

this is false ^.^ lol