Common work - 9th grade (14y) - examples
Group of workers washing half of the windows of the building in two hours. How long will take half the workers wash all the windows of the building?
A man drinks a barrel of water for 31 days, woman for 58 days, for how many days they drink barrel together?
- Painter Pavel
Painter Pavel painted the fence for 20 hours and painter Petr the same fence painted for 17 h. How long should take painted the fence together?
Fields go plow two tractors with various performance. The first tractor plow whole field in 5 hours, the second tractor plow whole field 5 hours longer. How long take plow whole field with two tractors?
- Road repair
Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
For every 5 minutes writes Dana 10 invitations, while Anna 14 invitations. How long will write together 120 invitations?
During the spring cleaning ladies going to wash windows. Mother takes wash all the windows 5 hours, the grandmother 3 times longer and Paula wash all windows in 5 hours. How many hours will spend washing the windows this "women's team" if working togethe
- Two workers
Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
Water pipe has a cross-section 1939 cm2. An hour has passed 567 m3 of water. How much water flows through the pipe with cross-section 300 cm2 per 14 hours if water flow same speed?
- Two typists
There are two typists who are rewriting the material 705 pages. First can it handle rewrite yourself for 24 days; the second 12 days. First typist wrote material yourself 4 days rest rewrites yourself second typist. How many days will it take rewriting alt
An oil tanker can be emptied by the first pump in 4.4 hours. Second pump can empty an tanker in 7.8 hours. If the first pump started at 8:00 and second 1.4 hour later, at what time will the tanker be empty?
Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators?
Marie earns 1.8 liters of blueberries for 1.2 hours, Peter 2.6 liters for 1.2 hours. How long have earns together one liter?
- Parquet floor
Three workers laid parquet floor for 3.646 hour. The first one would do this work alone 11 hours, the second in 12 hours. For how many hours would fulfill this work the third worker, if he worked alone?
- 5 pumps
Five pump to pump 3 hours 1600 hl of water. How long pumped same amount of water 4 pumps?
The first harvester reaps the grain from land for 24 hours, the second harvester for 16 hours. For how many hours will take harvest by two harvesters, but the second harvester started working four hours later than the first?
- Digging companies
Company A would dig a pit for 12 days, company B for 15 days, company C for 20 days and the company D for 24 days. Work began together companies C and D, but after three days joined them other two companies. How long took to dig a pit?
- 4 pipes
The tank flows out by 4 pipes in 6 hours 120 hl water. How much water flows out of 5 pipes of the same diameter in 14 hours?
The first tributary fill pool with water in 15 hours. The second tributary fill pool in 10 hours. For how many hours the pool is filled with both tributaries?
- Two diggers
There are two diggers. One digger digs a pit 83 hours second gidding 1.4 times faster. a) how long took to dig a pit second digger b) how long took dig together