Question 185797
The trick here is to find the prime factors in each total. Since the same number of kids bought soda AND candy, any factor that shows up in both numbers is a candidate. In this case, there is only one factor common to both 336 and 245. So that is the correct number of kids.

Find the prime factors and you're there. 
Use this URL to check your answer if you need to.
http://www.virtuescience.com/prime-factor-calculator.html