Time - examples - page 9

  1. Tourist
    map Tourist walk at 5.6 km/h. Every 5 km have 10-minute break. How many kilometers passed, when started at 4:00 and finished at 15:20?
  2. Mother and daughter
    mom_daughter Three years ago mother was three times older than daughter. After nine years she will be only twice old. How old is mother (and daughter)?
  3. Painters
    painter First painter painted fence himself for 12 hours, the second painter 3 hours sooner than first, and the third painters slowest up to 20 hours. How long took them paint fence if worked together?
  4. Father and son
    father_sin Father is three times older than his son. 12 years ago father was nine times older than the son. How old are father and son?
  5. The professor's birthday
    prof_einstein Professor of mathematics had 36 birthdays. The director congratulated him. The professor asked the director: "And how old are you?" The director replied: "I'm exactly twice as many years than you were when I was old as to you today." How old is the direc
  6. Paul and Honza
    tchata Honza went to chat on a bike without a break 3.0 hours. Paul the same way without breaks 30 minutes longer. The difference between the speeds of the two boys was the one kilometer per hour. How fast was Paul, if you know that the speed of the boys did not.
  7. Invitations
    envelope For every 5 minutes writes Dana 10 invitations, while Anna 14 invitations. How long will write together 120 invitations?
  8. Train from Brno
    train_cd First train started from Brno at 8 am at 60 km per hour. Second train started from Opava at 7 o'clock at the speed of 40 kilometers per hour. In how many hours and how far from cities trains meet when the distance of cities is 200 kilometers.
  9. Simple interest 2
    coins-uk Find the simple interest if 2531 USD at 2.5% for 9 months.
  10. Velocity ratio
    rov_kontinuity Determine the ratio at which the fluid velocity in different parts of the pipeline (one part has a diameter of 5 cm and the other has a diameter of 3 cm), when you know that at every point of the liquid is the product of the area of tube [S] and the fluid.
  11. A family
    smetiarske_auto A family of four pays for garbage collection per year 1800 Kč. How many crowns a year the waste company get from the house where lives 93 people?
  12. Knight
    jazdec Knight passed 25 km long track in 50 minutes, what was his average speed?
  13. Peleton
    tdf6 Cycling race was run at an average speed of 33 km/h. One cyclist lost with defect 6 minutes. How long and how far he must go at speed 38 km/h to catch peleton again?
  14. Minute hand v2
    clock_2 In how many minutes describe the minute hand angle 60 degrees?
  15. Divers
    diving 24-member group of divers carries the air for 11 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?
  16. Minute-hand
    hands How long distance will travel a large (minute) hand on the clock for 39 minutes, if its length is 33 cm?
  17. Walkers
    chodci From points A and B simultaneously started against each other two walkers. After meeting both continue to B. Second walker came to B 1.8 hours before the first walker. It's speed is 2.9 times of speed of the first pedestrian. How many hours went pedestr
  18. Pumps 3
    pump_water Two pumps of the same power fill the garden pool for 10 hours. How many of these pumps would have to use if we want to shorten the filling of the pool to four hours?
  19. Half life
    Bi Determine the half life of bismuth, when bismuth weight from the original weight of 32 g was only 2 grams in 242 minutes.
  20. Painting
    natieranie Jožko with Fero painted the bench for four hours. How many hours would take work if four friends help him?

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