Given the relationship “10 arms for every 8 eyes”, if there are 30 arms, how many eyes are there

Answer 1

Let's take this problem and turn it into a ratio: 10 arms : 8 eyes, or 10:8.

Simplifying this ratio (by dividing by 2) gives us 5:4. <--our target ratio

The number of eyes needed must satisfy the ratio. So, it becomes

10:8 and 30:x

Since arms increased by a factor of 3 (10x3 = 30), let's see if a factor of 3 will work for the eyes as well.

take 8x3 = 24, and put it into the new ratio -> 30:24. This ratio must simpify to 5:4.

By dividing 30 and 24 by 6, we get the simplified ratio of 5:4, which is our target!

Therefore, if we have 30 arms, there will be 24 eyes