Harmonic mean - practice problems - page 9 of 10
Number of problems found: 199
- Two pumps
The first pump fills the tank in 24 hours, and the second pump fills the tank in another 40 hours. How long will it take to fill the tank if it operates both pumps simultaneously? - Three drivers
Three drivers driving in the same direction found that they had the same amount of gasoline. The first is enough to go 6 km, 4 km, second and third 3km. Gasoline they divided, so all three just drove to the nearest petrol station. How many km away was a p - By dosing
A dairy uses a new and an old line to dose yogurts. By dosing yogurts on the old line, the order is fulfilled in 6 hours. If both lines work together, they will fulfill the same order in 2 hours. How many hours will it take to fulfill such an order if the - Forth and back
The car drives from point A to point B at 78 km/h speed and back at 82 km/h. If I went there and back at a speed of 81 km/h, the journey would take five minutes less. What is the distance between points A and B?
- Tributaries
The first tributary fills the pool with water in 15 hours. The second tributary fills the pool in 10 hours. For how many hours is the pool filled with both tributaries? - Boots
Master shoemaker has three apprentices. First, do one pair of boots for two days, second for one day, and third for 1.5 days. How long would it take to make a couple of boots if they worked together? - Simultaneously 2570
Two cyclists will set off simultaneously from one place on the circular cycling track. How long before they meet? Do you know that Karel will drive in 6 minutes and Laco in 10 minutes? - The dam
The water reservoir is filled with the first tributary for 25 hours and the second tributary for 35 hours. Sometimes, both inlets open, then a second tributary closed, and they filled the tank in four hours. What time does water flow from both tributaries - Grass garden
Mr. Grass would mow the garden for 5 hours, and his son Michael could do it for 7 hours. They agreed to wake up at 5 AM and begin to mow together. Ms. Grass needs to drive into town at 8:30. Michael says that at that time, they're done with work. Is he ri
- Two workers
Two workers work together and perform the job in 12 hours. If one has done half the work and then the second worker does the next half of the work, it will take 25 hours. How long would it take to job them separately? - Annual income
The annual income (in thousands of $) of fifteen families is 60, 80, 90, 96, 120, 150, 200, 360, 480, 520, 1060, 1200, 1450, 2500, 7200. Calculate the harmonic and geometric mean. - Painters
The first team of painters would paint the bridge in 15 days, the second in 10 days. After three days of working together, the second team goes out and continues only with the first team. How many days took the second team to finish painting the bridge? - Two diggers
There are two diggers. One digger digs a pit 77 hours per second, digging 1.2 times faster. a) how long did digging a pit with a second digger take? b) how long did it take to dig together? - Pedestrian up-down hill
The pedestrian goes for a walk first on the plane at 4 km/h, then uphill at 3 km/h. Then it is in the middle of the route, turns back, and goes downhill at 6 km/h. The total walk was 6 hours. How many kilometers went pedestrians?
- Garden
Father dug up the garden in 19 few hours. Son in 23 hours. How many hours does it take to dig up the garden together? - Fire tank
The whole fire tank was discharged once in 4 days, first out by a second in $n day. Once firefighters pumped out 4/16 of water from the tank, they let the water flow out both drains. How long does it take to empty the tank? - Painter Pavel
Painter Pavel painted the fence for 16 hours, and painter Petr painted the same fence for 13 h. How long should it take to paint the fence together? - Three workers
Three workers, A, B, and C, must work on a specific task. Workers A and B completed the task in 22 days, B with C for 10 days, and A with C for 19 days. How long would it take to complete the task for everyone alone? How long would it take to complete the - Blueberries
Marie earns 2.2 liters of blueberries for 1 hours, and Peter 2.5 liters for 1.5 hours. How long do they pick one liter together?
There are three machines in the workshop. The first treats 250 parts for 4.7 hours, the second treats 300 parts for 1.9 hours, and the third treats 230 parts for 4.6 hours. How long will it take to make 3100 parts if all three machines are worked simultanDo you have unsolved problem that you need help? Ask a question, and we will try to solve it. Solving math problems.
