Time + harmonic mean - practice problems
Number of problems found: 144
- Avg velocity
A car travels 120 km at 60 km/hr and another 120 km at 40 km/hr. What is its average speed? - Four legs of journey
A car driver covers a distance between two cities at a speed of 60 kmph and on the return, his speed is 40 kmph. He goes again from the first to the second city at twice the original speed and returns at half the original return speed. Find his average sp - Avg speed 2
A car covers four successive 3 km stretches at 10 kmph, 20 kmph, 30 kmph, and 60 kmph, respectively. What is the average speed over this distance? - A train 5
A train travels from Brno to Ass at a speed of 45 km/h and returns back at a speed of 36 km/h. Find the average speed of the train.
- Automobil The car traveled three quarters of the total journey at a speed of 90 km/h and the remaining part of the journey at a speed of 50 km/h. Find its average speed.
- Three workers
Three people - A, B, C . A and B can do a piece of work in 18 days, B and C can do it in 24 days, A and C can do it in 36 days.In how many days B alone can finish the work? - Rasmus Rasmus goes from station A to station B at the speed of 40km/h and returns B to A at the speed of 60 km/h. Find his average speed.
- One hour
If a pipe can fill a tank in 5 h and another pipe can empty the tank in 10 h, if both pipes are opened simultaneously, how many parts are filled in 1 hour? - Three pipes PPM
Pipe A can fill a tank in 20 h while pipe B can fill it in 10 h and pipe C can empty the full tank in 30 h. If all the pipes are opened together, how much time will be needed to make the tank full?
- Two men
2 men or 3 women can do a piece of work in 45 days. Find, in how many days 6 men and 1 women be able to complete the same work. - A piece of work
12 men or 18 women can do a piece of work in 14 days, then how long 8 men and 16 women take to finish the work? - A boat
A boat covers 20 km in an hour downstream and covers the same distance in 2 hours upstream. Then, find the speed of the boat in still water and the speed of the stream. - Decoration
Jarka and Jana decided to decorate their common room. If Jarka painted it alone, it would take her 4 hours, and Jane 3 hours. How long would they paint the room if they painted together? - Corrects 83017
The new teacher corrects papers for 9 hours, and the older one fixes them in 6 hours. How much will they repair together?
- Together 82965
An older digger would dig a ditch by himself in 6 hours. A younger digger can handle the same trench in 3 hours. How long would it take them to dig if they worked together? - Companies 82884
The K+S company will mow the meadow in ten hours. The Kosačka company mows the meadow in six hours. How many hours would these companies mow one such meadow if they worked together? - Simultaneously 82806
An empty tank is filled with inflow in 30 minutes. A full tank is emptied in 75 minutes with an open drain. How long does it take for an empty tank to fill up if both the inlet and outlet are open simultaneously? - Excavators 82208 Two excavators dig a pit in 12 days. How much shorter will this job take if 8 excavators dig the hole? In 3 or 9 days?
- Throughout 82075 In the metro, trains run in one direction at the same speed and the same intervals. Yesterday, there were 24 trains throughout the day. More trains will run today, as the time interval between trains will be shorter by 20%. How many more trains will there
Eva sews a costume in 6 hours, Ivana in 8 hours, and Monika in 4 hours. How long will it take them to make the costume if they work together?Do you have homework that you need help solving? Ask a question, and we will try to solve it. Solving math problems.
