Time + prime numbers - examples

  1. Racing track
    racing_track On the racing track circling three cars. The first passes one circuit for 8 seconds, the second for 16 seconds and a third for 15 seconds. a) Calculate number of seconds since the start to catch all three cars together for the first time again across the.
  2. Grandson and granddad
    vnuk_dedo Grandson with grandpa they counted how many years have together. Their product is 365. How many years is the sum of their years.
  3. Two months
    mars with moons Mars has two months, Phobos and Deimos. Phobos orbits around Mars in 7 hours 39 minutes and Deimos in 30 h 14 min. How long will repeat the relative position of the three celestial bodies?
  4. Digits of age
    babka The product of the digits of Andrew age as 6 years ago and not equal to 0. Andrew age is also the smallest possible age with this two conditions. After how many years will be the product of the digits of Andrew age again the same as today?
  5. Buses 4
    bus4 intervals: 1st bus 40 min. 2nd bus 2h 3rd bud 20min How long take them to meet - as soon as possible?
  6. Tram stop
    tram_historic At the tram stop met tram No. 4 and no. 5 at 10 AM. Tram no. 4 runs every 5 minutes, tram No. 5 at an interval of 7 minutes. How many times will meet until 12 o'clock?
  7. Buses
    buses_london At the bus stop is at 10 o'clock met buses No. 2 and No. 9. Bus number 2 runs at an interval of 4 minutes and the bus number 9 at intervals of 9 minutes. How many times the bus meet to 18:00 local time?
  8. Runners circle
    runners Pepa circles the track in 36 seconds. Kamil in 42 seconds. They started together. How many seconds will meet again at the start?
  9. Ships
    Ever_Given_container_ship Red ship begins its circuit every 30 minutes. Blue boat begins its circuit every 45 minutes. Both ships begin their sightseeing circuit in the same place at the same time always at 10:00 o'clock. a / What time does meet boat again? b / How many times a da
  10. Trams 2
    trams_1 Square passes two lines of tram. One running every nine minutes, a second interval of 15 minutes. Exactly at 12 o'clock arrived two tram lines in the square. How soon should a similar situation arise again?
  11. Two friends
    beers Two friends met as a good man perish together for a beer. After recovery the most important topics (politics, women, football ...), one asks: - And how many do you have children? - I have 3 children. - And how many years have? Friend already not want to an
  12. Bus lines
    bus27 Buses connections are started from bus stop on its regular circuit as follows: No. 27 bus every 27 minutes and No.18 every half hour. What time started this two bus lines run if the bus stop met at 10:15 am.?
  13. Trams
    tramvaje Two trams started at the same time from the same place. One tram journey takes 30 minutes and the second 45 minutes to its final stop. How long will trams meet again?

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