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How many robots are needed if 300 chairs have to be built from 2:00 p.m. to 7:00 p.m....
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First, lets see how much time the robots total took. Since the rate of robots is measured in minutes, lets changed the number of hours into minutes.
7-2 = 5 HOURS= 5*60= 300 minutes
so every robot worked 300 minutes.
Let's see how many chairs can one robot build in 300 minutes
300/4 = 75 chairs
the total robot team built 300 chairs.
Inevitably, there are 300/75 = 4 robots in the team
The final answer to this MC is D (4 robots).
Actually, this could be solved by plugging in method. However, i prefer to use algebra.
Posted by shaznl1 on July 29, 2011 at 8:00 AM (Answer #1)
The chairs are to be built from 2:00 p.m. to 7:00 p.m. That is a time period of 5 hours or 5*60 = 300 minutes.
The number of chairs to be built is 300. This essentially means that 1 chair should be built in a minute.
As each robot takes 4 minutes to build a chair, 4 robots are required to be able to build 4 chairs in 4 minutes or 1 chair in 1 minute.
The correct answer is option D or 4 robots.
Posted by justaguide on July 29, 2011 at 12:49 PM (Answer #2)
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