I am going to show you a video I found on youtube will provide you with many tricks/puzzles to solve, they are extremely hard, VERY HARD. IF you solve at least 5, you will be a legend.
If you are good in maths, you will know straight away.
some steps I advice you to use:
1_keep concentrating on the numbers, how they move.
2_try and draw diagrams on a paper.
3_FIGURE THEM OUT, GOOD LUCK .
it's pretty addictive.
Link to video: https://www.youtube.com/watch?v=Vefp3ITBu1I