Is 1.5 Rational?

[strabismus]

I don't think 1.5 represents a rational number. It stands for any real number between 1.45 and 1.549999999 expressed to 2 significant figures. It does not have the same meaning as 3/2.

[Prudie]

1.5 is exactly 1.5 and 3/2 and is rational. It does not stand for the approximations.

[Calibax]

Yes it's rational because it can be defined as a ratio 3:2 (3/2)

[Peter Pedant]

yes deffo rational

1.5 and 1.49 recurring are the same number

take one away from the other, and you get (1/10) power n ( x say )
and as n tends to infinity , X tends to zero and the two numbers merge into the same one - to wit 1.5

this is a branch of math called analysis and you can do college courses in it or access progz/lectures on U tube

[Buenchico]

While the use of 1.5, 1.50, 1.500, etc can, under certain circumstances, infer different levels of accuracy, that doesn't change the fact that (numerically) 1.5 = 1.50 = 1.500, etc and that they're all equal to 3/2.

So 1.5 is the DECIMAL REPRESENTATION of a rational number. However, in itself, it can't truly be said to be a rational number as it's not expressed in the 'a/b' format with which such numbers are usually written. (i.e. if an exam question says "Express 1.5 as a rational number" the expected answer is clearly "15/10" or "3/2" and "1.5" would almost certainly be marked as incorrect).

[fiction-factory]

I typed a long reply but see PP and Bunenchico have covered it.

You say 1.5 stands for any real number between 1.45 and 1.549999999 expressed to 2 significant figures. That is not the same as saying 1.5 is the same number as any other in the range. Your choice of 2 significant figures is a non-sequitur. Why 2 sig figs?

The only number other than 1.5 that equals 1.5 = 1.49999999.... recurring

[atalanta]

Surely, one-and-a-half is one-and-a-half, isn't it ?