Question

There are ______ rational numbers between any two rational numbers

Answer 1

There are infinite rational numbers between any two rational numbers.

For example:

Let $a=1$ and $b=2$ be any two rational numbers.

Then, $1<1.1<1.2<1.3<......1.9<1.10<1.11<1.12<.........1.21<1.22<......1.1111111<1.1111112,.....<2$

There are infinite number between $1$ and $2$ whose decimal representation is terminating and also non-terminating and recurring.

Hence, There are infinite rational numbers between any two rational numbers.