Equation - examples - page 15

  1. Father and son
    family_17 Father is 48 years old, son 23. When will be the father twice older than a son?
  2. Variations 3rd class
    cubic From how many elements we can create 13,800 variations 3rd class without repeating?
  3. The hall
    lucerna The hall had a rectangular ground plan one dimension 20 m longer than the other. After rebuilding the length of the hall declined by 5 m and the width has increased by 10 m. Floor area increased by 300 m2. What were the original dimensions of the hall?
  4. Homework - jumps
    castle_children Sasha jumped 121 cm Peter 4 cm more than Jirka. Jirka 6 cm less than Misha. Misha 7 cm less than Filip and Filip half as much Sasha and Petr together. How far each jumped?
  5. Copiers
    copy The new copier copying a folder of papers 5 min. faster than the old. The operator used new, but out of toner and exchange took 5 min. In that time copied on the old. The whole work has been done for 9 min. How long would the work done only by old copier?
  6. Tree shadow
    tree2_1 Tree perpendicular to the horizontal surface has a shadow 8.32 meters long. At the same time meter rod perpendicular to the horizontal surface has shadow 64 cm long. How tall is tree?
  7. Logarithmic equation
    nat_log_ln Solve equation: log33(3x + 21) = 0
  8. Two workers
    safarik_stu Two workers make 138 parts/items. The first one produces 30% more than the second. How many items will each produce?
  9. Pytagoriade
    pytagoriada Two fifth-graders teams competing in math competitions - in Mathematical Olympiad and Pytagoriade. Of the 33 students competed in at least one of the contest 22 students. Students who competed only in Pytagoriade was twice more than those who just competed
  10. Landlord
    dukaty Landlord had 49 ducats more than Jurošík. How many ducats Jurošík steal landlord if the Jurošík now 5 ducats more?
  11. Workhorses
    work A team of colleagues done the work in 20 days. After adding 2 colleagues from the beginning the work was completed in 15 days. How many members has the colleague team?
  12. TV commercials
    ad_on_TV For the typical one-hour prime-time television slot, the number of minutes of commercials is 3/8 of the minutes of the actual program. Determine how many minutes of the program are shown in that one hour.
  13. Hiker and cyclist
    cyklo At 7 PM hiker started at 6 km/h to hike. After 3 hrs. later started on the same trip cyclist at speed of 15 km/h. After an hour of driving a flat tire and take him half hours to correct defect. At what time catch up cyclist with hiker?
  14. To the cinema
    tree Jane at 8 am got message that all 1093 school pupils will go to the cinema. Within 20 min she said it to the three friends. Each of them again for 20 minutes said to the other three. In this way the message spread further. At what time all the children in.
  15. Bases
    trapezoids_1 The length of the bases trapezium are in ratio 4:5. Length of midline is 15. How long are the bases of a trapezoid?
  16. Scouts
    icons Three scouts went on a three day trip. The second day went 4 km more than the first day. The third day went two times less than the first day. They went along 54 km. How many kilometers went every day together?
  17. Pocket
    bageta Mirka spent on a trip for gifts half pocket. For the third remain money bought a bagel. Six euros left her. How many euros had Mirka in pocket?
  18. Pool 2
    bazen_pritok The first supply by the pool fill for five hours and the second fill for six hours, drain should be drained for 15 hours. For how many hours the pool is full, when we open both inlet now and outlet open two hours later?
  19. Painting rooms
    palma_1 If Dano paint three hours daily given work he complete in 7.5 days. How many hours a day would have to work to finish the job 1.5 days earlier?
  20. Coffee
    coffee Coffee from the machine in the cup cost 28 cents. Coffee is 20 cents more expensive than the cup. How much is the cup?

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