Question

A dog’s tail is 2 inches long. Every year his tail grows by 5%. What will be his tail's length next year?

Answer 1

`2.1` inches

Explanation:

`1`. Start by representing `5%` as a decimal. To convert from a percentage to a decimal, divide the percentage by `100` and remove the "`%`."

`5%`

`=5-:100`

`=0.05`

`2`. Since the dog's tail is `2` inches long right now, to find its length next year, multiply `2` inches by `1.05`.

`2xx1.05`

`=color(green)(|bar(ul(color(white)(a/a)2.1color(white)(i)"inches"color(white)(a/a)|)))`

You may be wondering why I multiplied by `1.05` instead of `0.05`. The reason is that when you multiply by `0.05`, you are finding `5%` of the value. Whereas when you multiply by `1.05`, you are finding `105%` of the value.

Multiplying `2` inches by `1.05` allows you to retain the `2` inches you already have. If you multiplied by `0.05` by `2` inches, you would get `0.1` inches, which is impossible since in the question, it stated that the dog's tail grows `5%` per year, not decrease by `95%`.