Time + inverse relationship - math problems

  1. The farmer
    cow The farmer calculated that the supply of fodder for his 20 cows was enough for 60 days. He decided to sell 2 cows and a third of the feed. How long will the feed for the rest of the peasant's herd last?
  2. 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?
  3. Hectares of forest
    stromy 12 workers plant 24 ha of forest in 6 days. In how many days will 15 people and 12 people plant the same area?
  4. A lot of hay
    zajic Martin's grandfather weighed a lot of hay and calculated that for 15 rabbits it last in 100 days. How many days will this lot be enough for 25 rabbits?
  5. Worker's performance
    plot 15 workers paint 180 m fence in 3 days. In how many days will 9 workers paint a 360 m fence? We assume that each worker have the same, constant and unchangeable performance.
  6. Fast tourists
    tourist_1 If three tourists pass the route in 5 hours, how long will the same route take six equally fast tourists?
  7. Temporary workers
    work_1 Three temporary workers work in the warehouse and unload the goods in 9 hours. In what time would five temporary workers unload the same products?
  8. Eight masons
    time Eight masons will plaster a wall with an area of 1440 m2 in 9 days. They work 8 hours a day. How much area will plaster 6 masons in 4 hours?
  9. Six students
    painter Two pupils painted the class in four hours. How long will it take for six pupils?
  10. Blueberries
    blueberry 5 children collect 4 liters of blueberries in 1.5 hours. a) How many minutes do 3 children take 2 liters of blueberries? b) How many liters of blueberries will be taken by 8 children in 3 hours?
  11. Painters
    time Ten painters paint the school in 20 days. How many days do four painters paint the school at the same pace of work?
  12. Assembly parts
    machine Nine machines produce 1,800 parts on nine machines. How many hours will it produce 2 100 parts on seven such machines?
  13. Seven workers
    wood Seven workers clear the glade in 22 hours. How many workers would need to be done in 8 hours?
  14. Cook on gas
    lpg The gas cylinder will last for 30 weekends for 2 hours of daily cooking. How many days will we be able to cook on a new cylinder when we cook 3 hours a day?
  15. The work
    clock-night-schr_17 The work was to be done by 150 workers. At the beginning of their work, their number reduced by 40, which increased the time of work by 5 and 1/3 of the schedule. How long did work take?
  16. Pump
    pumps_9 680 liters of water were pumped in 8 minutes. How many liters was spent in 56 minutes?
  17. Pumps
    pumps_8 After the floods, four equally powerful pumps exhausted water from the flooded cellar in 6 hours. How many hours would take a drained out with three equally powerful pumps?
  18. Hay bags
    krav 4 cows eat 16 hay bags in 5 days. How many bags will eat 5 cows in 7 days?
  19. Five inlets
    pipe2_5 The tank can be filled with five equally powerful inlets. If the tank is filled by four of these inlets, it takes a total of 30 minutes to fill one-third of the tank. How many minutes does it take to fill an empty tank if it is filled with all five inlets
  20. A report
    work_4 Maricris can type a committee report in 5 hours. Jane helped Maricris and together they finished the report in 3 hours. How long would it take Jane to complete the report she had worked alone?

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