Time - 9th grade (14y) - examples

  1. Adam and Ben
    venn_diagram_3_2 When Ben is so many years old to Adam today, Adam will be 23 years old. When Adam was as old as Ben, Ben was two years old. How old is today Ben and Adam?
  2. Pond
    rybnik2_1 A pond with two open floodgates will emptied in 20 days. A larger floodgate will emptied whole pond in 30 days. For how long would he be emptied with a smaller floodgate.
  3. Acres
    plocha_1 Two hours 24 students harvested chestnuts on 36 acres. How many square meters harvested one student per hour?
  4. Father and son
    family_17 Father is 48 years old, son 23. When will be the father twice older than a son?
  5. Grandfather
    family_16 The grandfather is three years older than an grandmother. The average age of the grandmother, the grandfather and their seven grandchildren is 28 years. The grandchildren have a total of 105 years. Calculate how old is grandfather.
  6. Troops
    regiment Route is long 203 km and the first day first regiment went at an average speed 20 km/h and journey back 19 km/h. The second day went second regiment same route at an average speed 18 km/h there and back. Which regiment will take route longer?
  7. Logic
    blue-barrel A man drinks a barrel of water for 31 days, woman for 58 days, for how many days they drink barrel together?
  8. Painter Pavel
    pixla_s_farbou Painter Pavel painted the fence for 20 hours and painter Petr the same fence painted for 17 h. How long should take painted the fence together?
  9. Tributaries
    pritok The first tributary fill pool with water in 15 hours. The second tributary fill pool in 10 hours. For how many hours the pool is filled with both tributaries?
  10. Road repair
    workers_1 Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
  11. Monkey
    monkey Monkey fell in 31 m deep well. Every day her scramble 3 meters, at night dropped back by 2 m. On that day it gets hangover from the well?
  12. Invitations
    envelope For every 5 minutes writes Dana 10 invitations, while Anna 14 invitations. How long will write together 120 invitations?
  13. Ravens
    krkavec The tale of the Seven Ravens were seven brothers, each of whom was born exactly 1.5 years after the previous one. When the eldest of the brothers was 4-times older than the youngest, mother all curse. How old was seven ravens brothers when their mother cur
  14. Madams
    womans During the spring cleaning ladies going to wash windows. Mother takes wash all the windows 5 hours, the grandmother 3 times longer and Paula wash all windows in 5 hours. How many hours will spend washing the windows this "women's team" if working togethe
  15. Two workers
    Frog Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
  16. Clock
    hodiny How many times a day hands on a clock overlap?
  17. Two tributaries
    bazen_2 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?
  18. Painters
    natieraci Five painters painting the fence for eight days. How many days over will take work if paint the fence only four decorators?
  19. Parquet floor
    Parkett Three workers laid parquet floor for 1.957 hour. The first one would do this work alone 5 hours, the second in 9 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  20. Daily average
    weather_forecast Calculate the average temperature during the day, when 14 hours was 20 °C and 10 hours was 15 °C.

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