Answer:
40
Step-by-step explanation:
Since 30% of the bag is blue, you can setup the equation, [tex]\frac{3}{10}x=12[/tex] where x is the total number of gumballs in the bag because that is what you are looking for. Simplify and you get [tex]x=40[/tex]. Checking this you get [tex]12=12[/tex] which is true.
