Reason - examples - page 10

  1. 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
  2. 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?
  3. 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?
  4. 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?
  5. 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?
  6. 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.
  7. Classroom 3
    kids_1 How many children are in the classroom, where 13 children are higher than Lenka and 9 children lower than Lenka?
  8. Four-digit number
    numbers_1 Find also a four-digit number, which quadrupled written backwards is the same number.
  9. The body
    body_cubes The body on the figure consists of cubes with an edge length 6 cm. What surface has this body?
  10. 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?
  11. 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
  12. 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)?
  13. Trapezium zoom
    trapezium How many times increase area of trapezoid if all sides and altitude increase 5 times?
  14. Mom and daughter
    mother_and_daughter Mom is 30 years older than the daughter. What is the age difference between them in 35 years?
  15. Work
    dlazba.pg First paver pave pavement for 27 hours. Second for 27 hours. Started first paver and after 4 hours, join the second. How long will they finish pavement?
  16. Seven-segmet
    7segment Lenka is amused that he punched a calculator (seven-segment display) numbers and used only digits 2 to 9. Some numbers have the property that their image in the axial or central symmetry was again give some number. Determine the maximum number of three-d
  17. 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.
  18. Password
    codes The voltage station is every day changing the master password, which consists of three letters. Code generation process does not change and is based on the following procedure: The following letters (A) to (I) correspond to different numbers from 1 to 9. I
  19. Rectangle - parallelogram
    nieco It is given a rectangle that is circumscribed by a circle with a radius of 5 cm. The short side of the rectangle measures 6 cm. Calculate the perimeter of a parallelogram ABCD whose vertices are the midpoints of the sides of the rectangle.
  20. Tourist
    map Tourist walk at 4.1 km/h. Every 5 km have 20-minute break. How many kilometers passed, when started at 4:40 and finished at 10:30?

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