Tricky Mathematical Brainteaser #9: Can You Solve It?

Are you a puzzle master? A math genius? Then you are going to love this series of mathematical brainteasers. All you have to do is find the missing number - sounds easy right? Well give it a go and tell us how you do. 

In this challenge there are four circles. Each circle has four numbers outside and one inside. You have to study the relationship between these numbers and solve for the fourth circle where the number is missing.

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How did you go? Did you figure it out? We have the answer below so that you can double check if you are right but don't cheat if you havent worked it out yet! 

Test your friends and SHARE this challenging brainteaser with your friends and family!