This is a high school question so I'm assuming you know how this works if I explain it this way.
Basically you need to put % over % so 50/100 =
since you are trying to find out what is 50% of 24 you would put x/24
50/100=x/24 then cross multiple 100x=50x24 which is 1200
then you have to get x alone so divide both sides by 100
x=12
plug in to verify.
hope this helps.
