2018 AMC 8 Problems/Problem 12
Problem 12
The clock in Sris car, which is not accurate, gains time at a constant rate. One day as he begins shopping he notes that his car clock and his watch (which is accurate) both say 12:00 noon. When he is done shopping, his watch says 12:30 and his car clock says 12:35. Later that day, Sri loses his watch. He looks at his car clock and it says 7:00. What is the actual time?
Solution
We see that every 
minutes the clock passes, the watch passes 
minutes. That means that the clock is 
as fast the watch, so when the car clock passes 
hours, the watch has passed 
hours, meaning that the time would be 
See Also
| 2018 AMC 8 (Problems • Answer Key • Resources) | ||
| Preceded by Problem 11 |
Followed by Problem 13 | |
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| All AJHSME/AMC 8 Problems and Solutions | ||
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