Hi there!
In order to answer your question you’ll need to write an equation in which “X” would be the number of containers you need to sell :
4X - 28 = 20
This equation means that each container you sell gives you $4, you also need to subtract $28 because that’s the cost for making the cookies and the equation is equal to 20 because you want to make a $20 profit.
Now that your equation in written down, you can solve it by isolating “X” :
4X - 28 = 20
Add 28 on each side of the equation → 20 + 28 = 48
4X = 48
Divide each side of the equation by 4 → 48 ÷ 4 = 12
X = 12
Your answer is D): In order to earn a $20 profit, you need to sell 12 containers.
There you go! I really hope this helped, if there’s anything just let me know! ☻