| 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 |
Monday, September 24, 2012
You are given two hourglasses. One measures 4 minutes and one measures 7 minutes. How would you measure exactly 9 minutes?
Subscribe to:
Posts (Atom)