An engineer must test three space suits in two test chambers. Each suit must be tested for 1 hour at each of two pressures.
He takes 10 minutes to load a suit in a chamber, set the pressure, and start the test; 4 minutes to change the pressure in the chamber; and 10 minutes to unload a suit from a chamber.
Knowing that each chamber could contain only one suit at once, and since he can only do one load/unload at a time, can he manage to test the suits in less than 4 hours ?
Chamber 1:
Start time: Activity Duration
0 Load Suit 1 10
10 Pressure test Suit 1 @ Pressure 1 60
70 Change Chamber 1 pressure 4
74 Pressure test Suit 1 @ Pressure 2 60
134 Unload Suit 1 10
144 Load Suit 2 10
154 Pressure Test Suit 2 @ Pressure 2 60
214 Unload Suit 2 10
224 End Chamber 1
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Chamber 2:
Start time: Activity Duration
10 Load Suit 2 10
20 Pressure test Suit 2 @ Pressure 1 60
80 Unload Suit 2 10
90 Load Suit 3 10
100 Pressure test Suit 3 @ Pressure 1 60
160 Change Chamber 2 pressure 4
164 Pressure Test Suit 3 @ Pressure 2 60
224 Unload Suit 3 10
234 End Chamber 2
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Engineer:
Start time: Activity Duration
0 Load Suit 1 in Chamber 1 10
10 Load Suit 2 in Chamber 2 10
Rest
70 Change Chamber 1 pressure 4
Rest
80 Unload Suit 2 from Chamber 2 10
90 Load Suit 3 in Chamber 2 10
Rest
134 Unload Suit 1 from Chamber 1 10
144 Load Suit 2 in Chamber 1 10
Rest
160 Change Chamber 2 pressure 4
Rest
214 Unload Suit 2 from Chamber 1 10
224 Unload Suit 3 from Chamber 2 10
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Min. Time is 234 min = 3hrs 54min
makes sense to me
