SOLUTION: Ms.donelly keeps Alex and Landon after school to clean the 16 tables in her room .If Alex cleans them by himself he takes 21 minutes .If Landon does the job alone he takes 14 mins.

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Ms.donelly keeps Alex and Landon after school to clean the 16 tables in her room .If Alex cleans them by himself he takes 21 minutes .If Landon does the job alone he takes 14 mins.      Log On


   

Question 21302: Ms.donelly keeps Alex and Landon after school to clean the 16 tables in her room .If Alex cleans them by himself he takes 21 minutes .If Landon does the job alone he takes 14 mins.How long will it take if the two boys work together?
Answer by Photonjohn(42) About Me  (Show Source):
You can put this solution on YOUR website!
1/14 is the time for Landon to do the job.
1/21 is the time for Alex to do the job.
Together they can do the job in T minutes
1/14 + 1/21 = 1/T
solve for time T if two boys work together.