Question

roman has 2 red pencils in his backpack. if this is 25% of the total number of pencil bow many total pencil are in his backpack?

Answer 1

You know that the 2 red pencils represent 25% of the total number of pencils (100%) that are in the backpack. To determine the total number of pencils you can use cross multiplication:

25%____2 pencils

100%____ x pencils

Both relationships are at the same ratio, so that:

`(2)/(25)=(x)/(100)`

Multiply both sides by 100 to determine the value of x

`\begin{gathered} 100\cdot(2)/(25)=100\cdot(x)/(100) \\ 8=x \end{gathered}`

There are 8 pencils on his backpack.