Question

Does anyone know how to answer this? The Probability that you draw a mechanical pencil from a group of 25 mechanical and wooden pencils is 3/5. How many are mechanical pencils?

Answer 1

There are 15 mechanical pencils

Explanation:

Recall that the probability of drawn a mechanical pencil from a larger group is given by the quotient of the number of mechanical pencils divided the total number of pencils in the sample.

so that means:

`P=(x)/(25) \\`

being x the number of mechanical pencils and 25 the total of all pencils in the sample. Since they give as P as 3/5, we can solve for the number of mechanical pencils (x) using the equation:

`P=(x)/(25) \\\\(3)/(5) =(x)/(25)\\x=(3\,*\,25)/(5) \\x=15`

So there are 15 mechanical pencils in the sample.