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Sand Timers
You have two sand timers, which can show 4 minutes and 7 minutes respectively. Use both the sand timers(at a time or one after other or any other combination) and measure a time of 9 minutes.
Explanation :
No Best Answer on this question yet!Asked In : Sapient
| Step | Time | 4 minute timer | 7 minute timer |
| 1 | 0 min | Start | Start |
| 2 | 4 mins | Flip | 3 minutes left |
| 3 | 7 mins | 1 minute left | Flip |
| 4 | 8 mins | Stop | Flip (1 minute left) |
| 5 | 9 mins | Stop |
