I was asked a question , which I have not yet been able to solve. If you have an answer please post it here: Question: 3 friends sharing a room for rent Rs.75/- per month. They sent Rs.75/- to the landloard through their maid. The landloard took Rs.70/- and returned back Rs.5 /- The maid had a tea for Rs. 2/- and returned back Rs. 3/- to the friends, so that each one gets Rs.1/- back, now the 3 friends were calculating the whole thing , as they go Rs.1/- back they have individually spent only Rs.24/- each, which totals to Rs.24/- x 3 =Rs.72/- + Rs.2/- for the tea the maid had, so the total is Rs.74/- whereas they have actually spent Rs.75/-. Where is the 1 rupee?