Inverse relationship + time - math problems

Number of problems found: 71

  • Shoemaker
    shoes Both the shoemaker and his apprentice repaired his shoes. The apprentice worked for 6 days and repaired 10 pairs of shoes every day. The shoemaker did the same job in 4 days. How many pairs of shoes did the shoemaker repair per day?
  • Mr. Ben
    bricks Mr. Ben drives bricks to the construction site. If he drove three times a day, he would make bricks in 8 days. How many times a day would he go every day to be done 2 days earlier?
  • Book reading
    books_1 Susan thought, "If I read 15 pages a day, I will read the whole book in 8 days. “How many pages would she have to read a day if she wanted to finish the book on the 6th day from the start of reading? And how many pages does the book have?
  • A truck 2
    kamion2_0 A truck leaves home with building materials and makes a return trip every six days. To deliver all the materials, you need eight truck trips every month. How many trucks do you need?
  • 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?
  • Book reading
    kniha_tridni Suzan reads a book. If she read half an hour a day, she would read it in nine days. How many minutes does he have to read a day if he wants to read it three days earlier?
  • Five combers
    permutations_3 Five combers harvest 12 rows of strawberries in 4 hours. How many rows of strawberries will two combers harvest in 10 hours?
  • Six workers
    workers Six workers earned a total of CZK 12,600 per week on the construction site (5 working days). How much do 7 workers earn in 10 days with the same daily average salary?
  • 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?
  • Fast tourists
    tourist_1 If three tourists pass the route in 5 hours, how long will the same route take six equally fast tourists?
  • 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?
  • Three workshops
    workers_1 One workshop can complete the task in 48 days, the second in 30 days and the third in 20 days. In how many days would the task be completed if all workshops worked?
  • Hay bags
    krav 4 cows eat 16 hay bags in 5 days. How many bags will eat 5 cows in 7 days?
  • 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?
  • Thunderstorm
    storm-012_1 The sound travels 1 km in about 3 seconds. How far is the storm if there is a time interval of 8 seconds between lightning and thunder?
  • Two masters
    ucitelia_komplet The two masters will make as many parts as five apprentices at the same time. An eight-hour shift begins at 6 o'clock. When can a master finish the job to produce just as much as an apprentice for the whole shift?
  • Five pumps
    nadrz_14 The water tank is filled with two pumps in 48 minutes. How long would it take to fill it with 5 same pumps?
  • 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?
  • 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
  • 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?

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