What's the missing number here in this Pie ?

Missing no. is 6

Because all sectors having 10+11 = 21 4+17 = 21 8+13 = 21 15+ ? = 21 , so 6

The missing number is 6.The two numbers opposite each other always total 21 : 15 + 6 = 21.

Find the missing number in the image below.

By deducing the logic used in the table below, can you find the missing number?

Find the value of the missing number in the table below.