Using the numbers in the segments of the lower two circles, the numbers in the upper left circle equal the sum of the numbers in corresponding segments of the lower 2 circles, the numbers in the upper central circle equal the difference between numbers in corresponding segments of the lower 2 circles, and the numbers in the upper right circle equal the product of the numbers in corresponding segments of the lower 2 circles.

The average of the outer 3 numbers is written in the centre of the star. So, Missing Element = (9 + 11 + 7)/3 = 9.

Working from left to right and reading each pair of numbers as a 2 digit value, these values represent the sequence of multiples of 7, starting at 49 and finishing on 70. So, Missing Element = 0.

Logic (Column-wise): Central Number = Difference of the sum of the bottom two numbers and upper two numbers. So, 8 = (3 + 9) - (1 + x) 8 = 11 -x x = 3. Missing Element = 3.

Working through the diagram in rows, and reading each row as a whole number, the diagram represents a subtraction. 203 - 7 = 196. So, Missing element = 6.

Starting with the top left number, and working down one row at a time, alternating between left and right, double the number each time. Repeat this sequence, starting with the top right number.

Moving from left to right, add 6 to the first number to get the next one along, then 8, 10 and 12 to complete the sequence. So, Missing Element, = 27 + 12 = 39.

Divide the circle, horizontally and vertically, to give 4 quarters. The sum of the numbers in the segments of each quarter equals 11. So, 3 + x = 11 x = 8

Numbers in segments of the central circle equal the difference between the sum of the numbers in corresponding segments of the left two and right two circles.

Reading the top and bottom lines as 2 digit numbers, multiply these together to give the 3 digit result, written in the middle. Thus, 23 * 34 = 782. Missing Element = 2.

Numbers in the segments of the lower left circle equal the sum of the digits in corresponding segments of the upper circles. Numbers in the lower right circle equal the difference between numbers in corresponding segments of the upper circles.

The sum of the 4 digits at the corners of the diagram is 17, as is the sum of the 4 digits in the middle of each side of the diagram. So, 17 = x + 8 + 4 + 3. x = 2. Missing Number = 2.

Starting at the top left and moving down, then to the right and up, in a snakes and ladders pattern, add the first two numbers together and subtract 1 to get the next in the sequence. So, Missing Number = 22 + 35 - 1 = 56.

Logic: Lower Segment Element = Left Element + Right Element - 2 So, 6 + x - 2 = 5 x = 5 - 4 x = 1. Missing Element = 1.

Logic (Row-wise): Sum of each Row element = 18. So, 18 = 0 + 6 + 5 + x. x = 7. Missing number = 7.

Clock-wise: First Square: 2 + 3 + 6 + 9 = 20. Second Square: 6 + 7 + 3 + 3 = 19 Fourth Square: 6 + 9 + 1 + 1 = 17 Third Square: 1 + 3 + x + 5 = 18 x = 18 - 9 = 9. Missing Number = 9.

Divide the whole diagram into 4 equal quarters, each comprising of a 3x3 square. The sequence of numbers in the top left quarter is repeated in each of the other quarters, but increasing by 1 each time as you move clockwise.

7 - 3 = 4. 9 - 3 = 6. So, 12 - 3 = 9.

Logic ( Top to Bottom): Sum in the row increase by 5. 5 7 + 3 = 10 5 + 8 + 2 = 15. So, 9 + 6 + 4 + 1 = 20 x = 1.

Logic: Third number = Sum of previous two numbers - 3. So, x = 29 + 45 - 3 = 71. Missing number = 71

Starting in the top left and moving in a Z shape around the diagram, each number equals the sum of the previous 2 numbers. So, Missing Number = 16 + 26 = 42.

In each row of the diagram, the sum of the left and right hand digits, minus the central digit is always 8. 11 + 5 - 8 = 8 12 + 10 - 14 = 8 7 + x - 3 = 8 x = 4. Missing Element = 4.

The numbers in the segments of the top left circle equal the sum of the numbers in corresponding segments of the lower two circles, and the numbers in the top right circle equal the difference between numbers in corresponding segments of the lower two circles.

Starting at the top left and working down, then to the right and up, and finally to the right and down in a zig-zag shape, numbers follow the repeated sequence, subtracting 1 then adding 3 etc.

Working in rows from top to bottom, the sum of the digits in each row increases by 2 each time, from 20 to 30. So, Sum of the last row = 30 9 + 9 + 2 + 1 + 5 + x = 30 x = 30 - 26 = 4. x = 4.

Working in rows, the number in the central box equals the sum of the left and right hand numbers, divided by 3. So, Missing number = (7 + 2)/3 = 3.

Logic: Next Number = Previous Number *2 - 4. Missing number = 36 *2 - 4 = 72 - 4 = 68.

The sum of the numbers along each side of the triangle is always 11. So, x + 2 + 5 = 11. x = 11 - 7 = 4.

Logic (Clock-wise): Sum of the outer element of the triangle = Central digit of next triangle. So, Sum of the outer digit of the Second triangle = Central digit of the third triangle. x = 8 + 1 + 0 x = 9. So, Missing Number = 9.

Left to Right, numbers increase by 3, then 2, then 1 after this it will start repeating the pattern. 5 + 3 = 8. 8 +2 = 10. 10 + 1 = 11. Now, pattern will repeat. 11 + 3 = 14. 14 + 2 = 16. So, Missing number = 16.