Proportions are very simple once you get the hang of them! What you do is cross multiple. :)
1. x/8=5/16
You first start by multiplying x and 16
Then multiply 5 and 8
So now you have 16x=40
Finally divide 16 from each side
You get: x+0.4!
2. 5/12=15/x
Remember to cross-multiply!
Now we have 5x=180
Next divide 5 from each side
You get: x=36!
