Find the missing number?

Solution(By Examveda Team)

Starting with the 3 circles in the top row, add together values in corresponding segments of the left and right hand halves of the left hand circle, and put the results in corresponding segments of the left hand half of the central circle.

Repeat this pattern for the left and right hand segments of the right hand circle.

For the lower row, follow the same pattern, but calculating the differences between values in the left and right hand halves of the left and right hand circles, putting the results in the central circle.