What is the value of y?

So me with this math problem. find the value of x the table shows the masses of 50 eggs. mass: 40-44 eggs: 6 mass: 45-49 eggs: x mass: 50-54 eggs: 12 mass: 55-59 eggs: 10 mass: 60-64 eggs: 7 mass: 65-69 eggs: 2 you!

And explain how you got it so i can understand future problems : 3

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