Examples for 9th grade - page 16

  1. 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?
  2. 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?
  3. Automaker
    car_manufactury The automaker now produces daily 4 new cars more than last year so the production of 360 cars will save just one full working day. How many working days to produce 360 vehicles needed last year?
  4. Height
    equilateral_triangle Calculate height of the equilateral triangle if its perimeter is 54?
  5. 4s pyramid
    pyramid_regular Regular tetrahedral pyramid has a base edge a=6 and collaterally edge length b=15. What is its height?
  6. Chocholate pyramid
    pyramid_choko How many chocolates are in the third shelf when at the 8th shelf are 41 chocolates in any other shelf is 7 chocolates more the previous shelf.
  7. Beer permille
    pivo In the 5 kg of blood of adult human after three 10° beers consumed shortly after another is 6.6 g of the alcohol. How much is it as per mille?
  8. Wheels
    tractor Small tractor wheel with a diameter of 60 cm must be rotated 8 times to overcome some pathway. How many times must turn the big tractor wheel with a radius 60 cm to overcome the same distance?
  9. Variations
    pantagram Determine the number of items when the count of variations of fourth class without repeating is 50 times larger than the count of variations of third class without repetition.
  10. Cyclist
    sagan A cyclist is moving at 26 km/h and follow pedestrian who is walking at speed 7 km/h. Walker has an advantage 13 km. How long take cyclist to catch up with him?
  11. Pairs
    pair At the table sit 12 people, 6 on one side and 6 on the other side. Among them are 5 pairs. Every pair wants to sit opposite each other. How many ways can they sit?
  12. Perpendicular
    perpendicular Determine the slope of the line perpendicular to the line p: y = 9x +7.
  13. Tractors
    tractor_2 Six tractors plowing the field for 8 days. After two days, two tractors broke down. How many days were prolonged work in the field?
  14. Sheep
    ships Shepherd tending the sheep. Tourists asked him how much they have. The shepherd said, "there are fewer than 500. If I them lined up in 4-row 3 remain. If in 5-row 4 remain. If in 6-row 5 remain. But I can form 7-row." How many sheep have herdsman?
  15. Hockey game
    Hockey In the hockey game was made 6 goals. Czech played against Finland. Czechs won 4:2. In what order to fall goals? How many game sequence was possible during the game?
  16. Three-digit numbers
    poker_hand_ranking How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)?
  17. The chord
    Tetiva Side of the triangle inscribed in a circle is a chord passing through circle center. What size are the internal angles of a triangle, if one of them is 40°?
  18. Copy typist
    pisaci_stroj Typist for 12 hours rewritten 15% of the manuscript. After how many hours he will done 35% of the manuscript?
  19. Dog
    dog_and_man Man goes with a dog on a long walk 18 km from the house. Man is walking at speed 5.3 km/h and a dog that constantly running between house and man at 17.1 km/h. How many kilometers will run the dog when they reach their destination?
  20. Prism X
    hranol The prism with the edges of the lengths x cm, 2x cm and 3x cm has volume 48000 cm3. What is the area of surface of the prism?

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