1 simple question on uniform composition

[Aakash Pandita]

what is the meaning of uniform composition?

I know that a solution or a mixture has uniform composition if all sections of it as the same properties.....

a solution like pure water can be called of uniform composition because it is made up of h2o molecules throughout and that is what we find when we keep on dividing it. but a mixture like salt and water has particles of nacl in between particles of h2o.

so why do we call it as of uniform composition?(as these nacl particles may be less and present between some h2o particles and present not in some others)