Thanks for the query.

The series is progressing + 4,- 3 again + 4, - 3 and so on. Therefore the series is => 72, 72 + 4, 76 - 3, 73 + 4, 77 - 3, ................... So, the next numbers are 74 + 4 = 78 and 78 - 3 = 75.

ans 78 and 75

78,75 ...alternate cycles