Posted by Devin on Wednesday, March 30, 2011 at 12:36pm.
Charlie can grade exams in 2 hours. It takes Mark 6 hours to grade the same exams. If they work together, how long will it take for them to grade the exams?

College Algebra  Devin, Wednesday, March 30, 2011 at 12:51pm
I figured it out. 40 minutes. Thanks anyway

College Algebra  Henry, Thursday, March 31, 2011 at 9:55pm
1/T = 1/2 + 1/6,
1/T = 3/6 + 1/6,
1/T = 4/6 = 2/3,
T = 3/2 = 1.5HRS.

College Algebra  chloe, Thursday, May 26, 2011 at 11:14pm
Angela cam comlete a project in 2 hours. it takes Jason 3 hours to complete the same project. how long will it take for them to complete the project together?
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