1. **Stating the problem:** Three girls paid $100 each, totaling $300, for a motel room. The clerk realized the correct charge was $250, so $50 was returned via the attendant. The attendant returned $10 to each girl ($30 total) and kept $20. Now, each girl has effectively paid $90, totaling $270, and the attendant holds $20. The question is: What happened to the missing $10? 2. **Clarifying the misunderstanding:** The mistake is in how the amounts are summed. The $270 total payment by the girls already includes the $20 kept by the attendant. The $270 consists of $250 (the correct room charge) + $20 (attendant's pocket). 3. **Correct accounting:** - The girls paid $270 total. - Out of $270, $250 went to the motel. - The attendant kept $20. The $30 returned to the girls (\$10 each) is not part of the $270; it's the difference from their initial $300. 4. **Conclusion:** There is no missing $10. Adding the $20 attendant's money to the $270 paid (instead of subtracting the returned $30) causes the confusion. The correct sum is: $$ 270 = 250 + 20 $$ where $250$ is the motel's charge and $20$ is the attendant's kept money. The $30 returned to the girls brings the total initial $300 balance. Therefore, no money is missing.