DSQ: Understanding work problems
Practice Questions
GMAT Quantitative Reasoning › DSQ: Understanding work problems
Steve can paint his greenhouse in 4 hours 40 minutes minutes, working alone; his brother Phil can do the same job in 6 hours, working alone. If they work together, to the nearest minute, how long will it take them?
A large water tower can be emptied by opening one or both of two drains of different sizes. On one occasion, both drains were opened at the same time. How long did it take to empty the water tower?
Statement 1: Alone, the smaller drain can empty the tower in three hours.
Statement 2: Alone, the larger drain can empty the tower in two hours.
Clara spent 
(1) Her salary was $3000
(2) She spent $1400 on rent and clothes
A large water tower can be emptied by opening one or both of two drains of different sizes. On one occasion, both drains were opened at the same time. How long did it take to empty the water tower?
Statement 1: Alone, the larger drain can empty the tower in three hours.
Statement 2: The smaller drain can empty water at 75% of the rate at which the larger drain does.
Last week, Mrs. Smith, Mrs. Edwards, and Mrs. Hume were able to write 
Today, Mrs. Smith is sick and cannot help, so Mrs. Edwards, and Mrs. Hume have to work without her. They must write 
Statement 1: Working alone, Mrs. Smith can write 
Statement 2: Working alone, Mrs. Hume can write 
Three brothers - David, Eddie, and Floyd - mow a lawn together, starting at the same time. How long will it take them to finish?
Statement 1: Working alone, David can mow the lawn in four hours.
Statement 2: Working together, but without David, Eddie and Floyd can mow the lawn in three hours.