Why is a variable used to represent a number?

Answer 1

because it can.

*Because if you want to create a rule. You wouldn't want to write it out, you would use it to abbreviate.

Example:

A blue whale will eat 4 tons of food each day, so if you wanted to know how many tons of food there are for any amount of days you could write the expression: 4*d where d= the number of days. So you can replace the d with any amount of days and you will get the correct answer!*

Hoped that helped!

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