The answer would be 64.
This is because if you notice each pattern is a multiple of the next natural number.
The first patter is 1 dot (the multiple is 1 x 1)
The second pattern is 4 dots (the multiple is 2 x 2)
The third pattern is 9 dots (the multiple is 3 x 3)
The fourth pattern is 16 dots (the multiple is 4 x 4)
The fifth pattern would be 25 dots (the multiple would be 5 x 5)
The sixth pattern would be 36 dots (the multiple would be 6 x 6)
The seventh pattern would be 49 dots (the multiple would be 7 x 7)
The eight pattern would be 64 dots (the multiple would be 8 x 8)
Hope this is a good explanation.
