Question

In taking a sampling of 12 marbles, youdiscover that 5 are cat's eyes. If you takeanother sample of 200 marbles, about howmany would you expect to be cat's eyes?English:Proportion: Answer must included answer to proportion

Answer 1

We know that

• From 12 marbles, you discover that 5 are cat's eyes.

This ratio would be

`\frac{12\text{marbles}}{5\text{cat eyes}}`

So, for 200 marbles we can elaborate a proportion to find the number of cat's eyes we expect.

`\frac{12\text{marbles}}{5\text{ cat eyes}}=(200marbles)/(x)`

Where x represents the cat's eyes. Let's solve for x

`x=(200\cdot5)/(12)=(1000)/(12)=(500)/(6)=(250)/(3)\approx83.33`

Therefore, for 200 marbles there must be 250/3 cat's eyes, or 83 of them, approximately.