SOLUTION: Crispin can clean the auditorium in 12 minutes while Tonio can do the job in 8 minutes. When Tonio arrived at the auditorium one day, he found Crispin already at work. IF the 2 wer
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-> SOLUTION: Crispin can clean the auditorium in 12 minutes while Tonio can do the job in 8 minutes. When Tonio arrived at the auditorium one day, he found Crispin already at work. IF the 2 wer
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Question 886770: Crispin can clean the auditorium in 12 minutes while Tonio can do the job in 8 minutes. When Tonio arrived at the auditorium one day, he found Crispin already at work. IF the 2 were able to finish cleaning the rest of the auditorium in 4 minutes, what part of the audiorium had Crispin finished cleaning when Tonio arrived? Answer by Theo(13342) (Show Source):
time for crispin to clean is 12 minutes.
formula becomes:
r * 12 = 1
rate for crispin to clean is 1/12 of the job per minute.
time for tonio to clean is 8 minutes.
formula becomes:
r * 8 = 1
rate for tonio to clean is 1/8 of the job per minute.
working together, crispin and tonio clean the rest of the job in 4 minutes.
their combined rate is (1/8 + 1/12) which is equal to (5/24) of the job per minute.
in 4 minutes they have cleaned 4 * 5/24 = 20/24 of the job.
this means that crispin must have already cleaned 4/24 of the job before tonio arrives.
