Practice Density of Numbers in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

The property that between any two distinct real numbers, there are infinitely many other real numbersβ€”no two are 'adjacent'.

No matter how close two numbers are, you can always find one between them.

Example 1

medium
Find three rational numbers strictly between \dfrac{2}{5} and \dfrac{3}{5}.

Example 2

hard
Show that there is an irrational number between 1 and 2, and find one explicitly.

Example 3

easy
Find a rational number between 0.3 and 0.4 by averaging, and another by finding a decimal with more places.

Example 4

medium
Are there integers between 3 and 4? Are there rationals? Explain what this says about the density of integers vs. rationals.