   SEARCH HOME Math Central Quandaries & Queries  Question from Allison, a student: It ask me to find an example of an irrational number less than -5 and I don't understand what the difference from a rational number and an irrational number besides the fact that a rational number can be repeated and shown in a simple fraction and an irrational number can't be written in a simple fraction. Can you help me? Hi Allison,

You have the essential facts about rational and irrational numbers correct with one small edit

A rational number can be written as a simple fraction and an irrational number can't be written in a simple fraction.

The "repeated" aspect is that when a simple fraction is represented in decimal form it has a repeated pattern, for example $\large \frac{17}{45} \normalsize = 0.3777 \cdot \cdot \cdot$ where the digit 7 is repeated.

You are to find an example of an irrational number which is less than -5. Can you give me any example of an irrational number?

Penny      Math Central is supported by the University of Regina and the Imperial Oil Foundation.