Three people

Three people start doing a work at a same time. The first worked only 2 hours. The second ended 3 hours before the end. On an individual basis, it would take the first time to do the work 10 hours, second 12 hours and 15 hours third. How many hours did it take to work together under these conditions?

Correct answer:

t =  7 h

Step-by-step explanation:

2/10 + (t-3)/12 + t/15 = 1

9t = 63

t = 7

Our simple equation calculator calculates it.

Did you find an error or inaccuracy? Feel free to write us. Thank you!


Tips to related online calculators
Do you have a linear equation or system of equations and looking for its solution? Or do you have a quadratic equation?
Do you want to convert time units like minutes to seconds?

You need to know the following knowledge to solve this word math problem:

Related math problems and questions:

  • Three tributaries
    bazen It is possible to fill the pool with three tributaries. The first would take 12 hours, the second 15 hours, and the third 20 hours. The day before the summer season began, the manager opened all three tributaries simultaneously. How long did it take to fi
  • Working together
    workers Two people will do the work in 12 days. They worked together for 8 days. Then only one worked for 10 days. How many days would each of them do the work if he worked alone?
  • Two workers
    work One worker needs 40 hours to do a job, and the second would do it in 30 hours. They worked together for several hours, then the second was recalled, and the first completed the job itself in 5 hours. How many hours did they work together, and how much did
  • Digging
    digging The first worker would dig a trench in 6 hours. For the second, the same work would take 4 hours. How long did it take for the trench to be dug if they worked together?
  • Three pumps
    pumps We are filling the pool. The first pump would be filled in 12 hours, the second pump in 15 hours. If all three pumps were running at the same time, it would fill the pool for 4 hours. How long would the pool fill only with the third pump?
  • Two workers
    mame_nizke_mzdy The first worker completed the task by himself in 9 hours, the second in 15 hours. After two hours of joint work left first worker to a doctor and the second finished the job himself. How many hours worked second worker himself?
  • Two tributaries
    bazen Two tributaries of the pool fill it in 10 hours. One of the tributaries would fill 15 hours. How long would fill the first tributary?
  • Together m+d
    painter Aunt Jane would paint her apartment in 10 hours, her mother in 15 hours. How much do they paint it for together?
  • Painters
    painters The first team of painters would paint bridge in 15 days, the second in 10 days. After 3 days of working together second team goes out and continue only first team. How many days took second team to finish painting the bridge?
  • Three painters
    painter One painter would have painted the fence for 15 hours, the second in 12 hours. The plot had to be painted in four hours, so they called the third one, and all worked together. For what time would the third painter paint fence the fence alone?
  • Bricklayers
    murar The first bricklayer would build a wall in 3 days, the second in 4 days. The first bricklayer worked alone for a day, then the second bricklayer came to his aid and they finished the work together. How long did it take to build the wall?
  • Two masons
    garage Two masons built the garage together - it took 18 days. If they worked independently, the other would work 15 days more than the first. For how many days would build the garage each mason himhelp?
  • Parquet floor
    Parkett Three workers laid parquet floor for 2.301 hour. The first one would do this work alone 7 hours, the second in 6 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  • Work together
    work Michal and Dorota would do the work together in 2.25 hours. If Dorota had to do it herself, it would have taken her 6 hours longer than Michal. Determine the time that Dorota would do the work herself and the time that Michal would do it himself.
  • Summer tires
    workers Three tire servants have to change the summer tires on 6 cars in 2 hours. Mark's replacement would take 4.5 hours, Jirka would do it in 3 hours and 10 minutes, and Honza in 4 hours. Will they be able to replace all tires at the desired time?
  • Two pumps together
    pumps The first pump will fill the tank itself in 3 hours and the second one in 6 hours. How many hours will the tank be full if both pumps are worked at the same time?
  • Harvesters
    kombajn The first harvester will harvest the grain from the field in 20 hours, the second, the more powerful in 10 hours. How long will it take to harvest this field by both harvesters if the second harvester has to be set up first and this takes 2 hours? The fir