1. **State the problem:** Three girls initially paid $300 total for a motel room, but the correct charge was $250. The clerk gives $50 to the attendant to return to the girls. The attendant gives $10 back to each girl ($30 total) and keeps $20 for himself. The confusion arises because the girls paid $270 ($90 each), and the attendant has $20: $270 + $20 = $290, seemingly missing $10. 2. **Analyze the payments:** Originally, the girls paid $300. 3. The correct cost of the room is $250, so the girls effectively paid $270 ($90 each). 4. Out of $270, $250 goes to the motel and $20 is kept by the attendant. 5. The mistake is adding $270 (girls' payment) plus the $20 (attendant's money). The $270 already includes the $20 the attendant took. 6. The correct sum is $250 (to motel) + $20 (attendant) + $30 (returned to girls) = $300 total original payment. 7. There is no missing $10; the error is in the misleading addition of $270 and $20. **Final explanation:** The girls paid $270 in total, which consists of $250 to the motel and $20 kept by the attendant. Adding the $20 again is double counting. Answer: There is no missing $10; the apparent discrepancy is caused by incorrect addition.