To solve this, we have to figure out how much each restaurant wants you to pay per shrimp. We could have done this multiple different ways, but look at the bottom. It clearly states PER SHRIMP. Why not figure it all out in one go, right? So, we divide the price by the amount by shrimp. Why do we do this? Think this way: We have a toy for 2 dollars. 2 toys will be $4, 3 toys will be $6. If we divide $4 by 2, we'll get our $2 per toy. The same thing goes for this problem. Let's start with A. 13.20 ÷ 8 = 1.65. Restaurant B: 18.00 ÷ 12 = 1.5. Restaurant C: 10.32 ÷ 6 = 1.72. Restaurant D: 13.05 ÷ 9 = 1.45. Let's look at the numbers we got! We want the lowest number because that'll be the best deal. Looking at our data, it's easy to see Restaurant D is the clear winner.
Restaurant D; 1.45.
Hope this helps!