Answer:
No worries if not, here's the explanation - ordered clockwise, the five numbers shown are four, seven, 13, 25 and 49, with a question mark over the final wedge.
The pattern here, working clockwise, is to do with the difference between one number and the next.
Starting with four and seven, the difference here is three, and the difference between each number doubles, as it goes from seven to 13, a difference of six, then 13 to 25, a difference of 12.
This goes on to a difference of 24 between 25 and 49, before finally working out that the final number is 97, having a difference of 48 from the previous number.