Skip to main content.

Hint to puzzle 52: Floor function sum

One approach is to first consider the result when n = 10.

For example, if x = 8.71 and n = 10:

[x] + [x + 1/n] + ... + [x + (n−1)/n] = [8.71] + [8.81] + [8.91] + [9.01] + [9.11] + [9.21] + [9.31] + [9.41] + [9.51] + [9.61].
  = (3 × 8) + (7 × 9).
  = 87.

[nx] = [87.1] = 87.