A men spent 1/4 of his monthly salary on rent 2 /5 on food and 1/6 on his children education. What fraction of his salary left.

1/4 + 2/5 + 1/6 = 15/60 + 24/60 + 10/60 = 49/60. What's left?

60/60 - 49/60 = 11/60 remains.