Final answer:
Between any two numbers on a number line, there is an infinite number of fractions, as fractions can be divided infinitely and infinitesimally.
Step-by-step explanation:
The question posed is: How many fractions are there between any two numbers on a number line? The answer to this is that there is an infinite number of fractions between any two numbers. This is because fractions can be infinitely divided; for instance, between the numbers 0 and 1, you can have fractions like 1/2, 1/3, 1/4, and so on, and even between 1/2 and 1/3, you can have 1/2.5, 1/2.75, etc. As with decimals, fractions can be refined to an indefinitely small value, and thus, infinite fractions can exist between any two points on a number line.