This is your last chance to solve it without help. Here is it again.
The correct answer is 52. How did we get to that solution?
The pattern is +0, +3, +8, +15, …..
i.e. + (1 x 1 – 1), + (2 x 2 – 1), + (3 x 3 – 1) + (4 x 4 – 1), …..
Therefore, the missing number = 28 + (5 x 5 – 1) = 28 + 24 = 52
Yep, that was pretty difficult. Yikes!