I've answered a similar question here: https://web2.0calc.com/questions/ice-cream_2 .
If you want, I can explain to you how exactly you can solve this question, but I think just reading my explanation (and the 2 other guests' explanations) will help. Good luck!
Here are the steps you can take to solve this problem.
1. Find the average of 1 ice cream cone. (360 divided by 6)
2. Mulitply the avarage by 7, since the problem wants you to find the cost of 7 ice cream cones.
If you follow these two steps, I'm sure you will get the correct answer. If you want me to explain further on why you should do these two steps, I can explain. Good luck!