Example: For every 3 boys, there are 4 girls.
Ratio: 3:4 also 3/4
How to use it?
Example question: If there are 3 boys for every 4 girls and there are 27 boys in the class, how many girls are there?
How to set up the ratio:
3 27
— = —
4 x
Solve it?
[Cross Multiply]
3x= 108
[Divide]
X= 36
How to check it?
Reduce 27/36 and see if it equals 3/4
OR
Plug both into the calculator and both should come out with the same decimal. In this case it is 0.75