Number Puzzles Questions

In each circle, starting at the  top left segment ,numbers increase, as you move clockwise,by 2 for the upper left circle,3 for the upper right, 4 for the lower right and 5 for the lower left

Sum of all numbers in each row and columns must be 15.

In last row to gt sum as 15 missing number must replaced by 1. 

Adding the corresponding numbers in first and last figures gives the corresponding number in the middle figure.

i.e, 4 + 3 = 7

13 + 2 = 15

2 + 4 = 6

9 + 1 = 10

We can make an equation:

3(100000 + x) = 10x+1

(Why? Well, adding 100000 puts a 1 at the front of a five-digit number, and multiplying by 10 and adding 1 puts a 1 at the end of a number)

Solving this gives:

10x+1 = 3(100000 + x)
10x+1 = 300000 + 3x
10x = 299999 + 3x
7x = 299999
x = 299999/7 = 42857

The answer is 42857 (142857 is three times smaller than 428571).