Engineering Board Exam Reviewer · Work Problems · hard
In a company, x can do a job 50% faster than y and 20% faster than z. If they work together, they can finish the job in 4 days. How many days will it take x to finish the job if he is to work alone?
- 18 days
- 10 days
- 12 days
- 16 days
Answer
B. 10 days
Solution
1/x=1.5≤ft(1/y ) and 1/x=1.2≤ft(1/z ), so 1/y=1/1.5x and 1/z=1/1.2x. Combining: 1/x+1/1.5x+1/1.2x=1/4, giving x=10 days.
More Work Problems questions
- Candle A and candle B of equal length are lighted at the same time and burn until candle A is twice as long as candle B. Candle A is…
- The average rate of production of a PCB is 1 unit for every 2 hours of work by two workers. How many PCBs can be produced in one month by…
- Mr. Yayama Nin can wash his car in 15 minutes, while his son Reese Kid takes twice as long to do the same job. If they work together, how…
- Pipes X and Y can fill an empty tank in 6 and 3 hours respectively. Drain D can empty a full tank in 24 hours. How long will an empty tank…
- Bing can finish a job in 8 hours. Bong can do it in 5 hours. If Bing worked for 3 hours and then Bong was asked to help her finish it, how…
- Bing, Bong and Bang can mow a lawn in 3, 4 and 6 hours respectively. What fraction (as a percent) of the yard can they mow in 1 hour if…
- A and B can do a piece of work in 60 days, B and C in 35 days, and A and C in 30 days. Working together, how many days can all of them…
- If 15 students can build a railway prototype 108 m long in 6 days, what length of similar railway can be built by 25 students in 3 days?
- Twenty-eight students can finish a certain design project in sixty days. At the start of the sixteenth day, five students dropped the…
- Marlon, Kimbert and Meryl can mow the lawn in 4, 6 and 7 hours respectively. What fraction of the yard can they mow in 1 hour if they work…