Reason - examples - page 10

  1. Three digits number
    plot How many are three-digit integers such that in they no digit repeats?
  2. Temperature calculus
    snowman Calculate percentage of temperature decrease if changed from -5 °C to -16 °C?
  3. Trickster
    cents_2 Figliarko has 13 cents less than Hana. Together they have 57 cents. How many cents has Hana and how many Figliarko?
  4. Tablecloth
    decka I embroider tablecloth in 20 days but if I embroider 3/4 hours a day I have embroider it for 15 days. How long do I embroider a day?
  5. David number
    numbers2_4 Jana and David train the addition of the decimal numbers so that each of them will write a single number and these two numbers then add up. The last example was 11.11. David's number had the same number of digits before the decimal point, the Jane's number
  6. Combi-triangle
    komb_triangle On each side of the square is marked 10 different points outside the vertices of the square. How many triangles can be constructed from this set of points, where each vertex of the triangle lie on the other side of the square?
  7. Cross-country competition
    spartakiada Cross-country competition was attended by 76% of pupils of class 9.B. Class consis of 16 boys, two of whom did not run and 4 girls did not run. How many girls go to class 9.B?
  8. Number train
    train2 The numbers 1,2,3,4,5,6,7,8 and 9 traveled by train. The train had three cars and each was carrying just three numbers. No. 1 rode in the first carriage, and in the last carriage was all odd numbers. The conductor calculated sum of the numbers in the first
  9. Coin
    mince How many 50-cent coins must be put in a row that next 50-cent coins after them (above) rolled on it axis?
  10. Divers
    diving 20-member group of divers carries the air for 15 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?
  11. Classroom 3
    kids_1 How many children are in the classroom, where 13 children are higher than Lenka and 9 children lower than Lenka?
  12. Forest ranger
    srny Forest ranger watching from the hide deers. At one time point he can see 6 deers. How many maximum deers can be see by 3 rangers at same time?
  13. Chicken
    sliepka I threw three chicken for a handful of grains and I noticed that it eat in a ratio of 8:7:6 and two of them grabbed 156 grains. How many grains have fought that chicken?
  14. Unions
    odbory_prdel Calculate how much money per year would go to the treasury of unions if 218 thousand employee join unions with an average net salary of 407 euros and if memberhip in union cost 1% of the net monthly salary.
  15. Four-digit number
    numbers_1 Find also a four-digit number, which quadrupled written backwards is the same number.
  16. Workman - shift
    favorit_skoda The worker produces 300 components per shift. How many components would be produced in 18 shift, if his performance gradually increased every shift by 3 components?
  17. Tunnels
    Mysky Mice had built an underground house consisting of chambers and tunnels: • each tunnel leading from the chamber to the chamber (none is blind) • from each chamber lead just three tunnels into three distinct chambers, • from each chamber mice can get to any
  18. The body
    body_cubes The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
  19. 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)?
  20. Mom and daughter
    mother_and_daughter Mom is 30 years older than the daughter. What is the age difference between them in 35 years?

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