Subject: Chef using hour glasses

Here is my quesiton,

How can a chef use an 11 minute hour glass and a seven minute hour glass to time a vegtable that needs to be steamed for 15 minutes.

I would appreciate the answer thank you,

Nathan

Hi Nathan,

Consider this:

As soon as the water starts to boil, begin the timing by running both hour glasses simultaneously. By starting them at the same time, the 7 minute hour glass will run out when the 11 minute hour glass still has 4 minutes left. When the 7 minute hour glass runs out, immediately turn it over and start it again. Now when the 11 minute hour glass runs out, the 7 minute hour glass will have been running for 4 minutes. If you turn the 7 minute hour glass over immediately upon the 11 minute hour glass running out, it will run for 4 minutes, for a total of 15 minutes altogether.

I will summarize this in a chart for you.

 Elapsed time Start both at the same time. 0 min. 7 minute hour glass runs out (restart 7 minute hour glass by turning it over) 7 min. 11 minute hour glass runs out 4 minutes later (turn over 7 minute hour glass again) 11 min. 7 minute hour glass runs out 4 minutes later 15 min.

Hope this helps,
Leeanne

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