Examples for 9th grade - page 32

  1. n-gon II
    x-gon_1 What is the side length of the regular 9-gon circumscribed circle of radius 13 cm?
  2. n-gon
    x-gon What is the side length of the regular 5-gon inscribed in a circle of radius 11 cm?
  3. Fertilizer
    okurky Mr. Gherkin use for fertilization 9% solution of fertilizer. 7 liters of it still left. How much water must be added to the solution to make only 5% solution?
  4. Train
    High-Speed-Train A passenger train traveled for 4 hours 136 km. 2.7 hours after its departure started fast train and caught it on 324 km. How many km/h is different its average speeds?
  5. Aircraft
    aircraft The plane flies at altitude 6800 m. At the time of first measurement was to see the elevation angle of 20° and second measurement of the elevation angle of 34°. Calculate the distance the plane flew between the two measurements.
  6. Quadrant
    quadrants In what quadrant is a 1501° angle?
  7. Cuboid
    cuboid Cuboid with edge a=14 cm and body diagonal u=42 cm has volume V=10976 cm3. Calculate the length of the other edges.
  8. Right triangle
    triangles_1 Right triangle ABC with side a = 16 and the area S = 80. Calculate the length of the remaining sides.
  9. Salary
    platy Calculate equivalent annual salary to hourly salary $ 29. Assume a 40-hour work week.
  10. Heron backlaw
    heron_math Calculate missing side in a triangle with sides 33 and 27 and area 118.3.
  11. Cylinder - basics
    cylinder Cylinder with base radius r = 37 cm and height h=74 cm. Calculate:
  12. Candy - MO
    cukriky_4 Gretel deploys to the vertex of a regular octagon different numbers from one to eight candy. Peter can then choose which three piles of candy give Gretel others retain. The only requirement is that the three piles lie at the vertices of an isosceles triang
  13. Cancer
    cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
  14. Numbers at ratio
    number-2_2 The two numbers are in a ratio 3:2. If we each increase by 5 would be at a ratio of 4:3. What is the sum of original numbers?
  15. Reducing number
    123 Reducing the an unknown number by 28.5% we get number 243.1. Determine unknown number.
  16. Traffic laws
    car_lights Under traffic regulations, car lights can illuminate the road up to a maximum of 30 m. To check the reach of the dipped-beam lights of their car, Peter stopped car at 1.5 m from the wall. The dipped-beam headlights are 60 cm high. At what height on the wa
  17. Mom and daughter
    family_1 Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter?
  18. angles in quadrilateral
    4uhelnik What size have angles in quadrilateral (4-gon) if they are in a ratio of 8: 9: 10: 13?
  19. Truck
    auto In 7 hours started from town Krnov truck at speed 40 km/h. Passenger car started against it in 8 hours 30 minutes from the city of Jihlava at speed 70 km/h. Distance between this two cities is 225 km. At what time and at what distance from Krnov this two.
  20. Salt
    sol 1 t of sea water contains 25 kg of salt. How many tons of seawater must be evaporated to obtain 2 q of salt?

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