Examples for 9th grade - page 24

  1. Cans
    konzervy How many cans must be put in the bottom row if we want 182 cans arrange in 13 rows above so that each subsequent row has always been one tin less? How many cans will be in the top row?
  2. Vinegar
    vinegar_1 What percentage vinegar we get if we mix 1 if dm³ eight percent vinegar with 1.5 dm³ six percent vinegar?
  3. The city 2
    kingkong Today lives 273000 citizens in city. How many citizens can we expect in 12 years if their annual increase is 2.5%?
  4. Inscribed triangle
    obluk To a circle is inscribed triangle so that the it's vertexes divide circle into 3 arcs. The length of the arcs are in the ratio 2:3:7. Determine the interior angles of a triangle.
  5. Pennies
    Toliar.preview 800 pennies have the same value as 100 ducats. 100 pennies have the same value as 250 tolars. How many ducats has the same value as 100 tolars?
  6. Snowman 2
    snowman_1 On the medal, which has the shape of a circle with a diameter 17 cm is sketched snowman so that the following requirements are met: 1. snowman is composed of three circles, 2. space over snowman is the same as under it, 3. diameters of all circles express
  7. Diamond
    rhombus2_2 Determine the side of diamond if its content is S = 500 cm2 and one diagonal u2 = 46 cm.
  8. Dried apples
    jablka_2 How many kilograms of fresh apples id needed to 120 kg of dried apples when from 0.4 tons of fresh apples we get 75 kg of dried apples?
  9. Disinfecting solution
    desinfect How much distilled water is necessary to pour into 500 ml of 33% hydrogen peroxide solution to obtain 3% disinfecting solution?
  10. Coffee
    arabica_robusta Coffee merchant has coffee robusta and arabica species. 1 kg Robusta worth 450 CZK, Arabica 1 kg is 300 CZK more expensive. Calculate how many kilograms of Robusta and Arabica will need to produce 30 kg of the mixture so that the mixture cost is 490 CZK p
  11. Probability - tickets
    zreby What is the probability that when you have 25 tickets in 5000 that you wins the first (one) prize?
  12. 3sides prism
    prism_3 The base of vertical prism is an isosceles triangle whose base is 10 cm and the arm is 13 cm long. Prism height is three times the height of base triangle. Calculate the surface area of the prism.
  13. Tank No 8
    tank1 Tank is filled by one inlet valve with a flow rate of 12 liters per second in 72 minutes. How long take the tank to fill, if we open half an hour after one more inlet?
  14. Ski tow
    ski_tow The ski club has 168 pupils and used lift with 60 seats, while students always follow the same sequence in filling seats. How many times while riding a ski lift skier sitting in the same seat as the first run?
  15. Deposit 3
    interest_money After a year had Martin on bank account € 1764. What was the interest rate when the initial deposit was € 1581?
  16. Alcohol 2
    alko Two types of alcohol one 70% and second 61% give 11 liters of 57% alcohol. How many liters of each type are in the mixture?
  17. Slope
    slope What is the slope of the line defined by the equation -4x -2y = -7 ?
  18. Cube in a sphere
    cube_in_sphere The cube is inscribed in a sphere with volume 6598 cm3. Determine the length of the edges of a cube.
  19. Motion
    cycling Cyclist started at 5:00 from point N to point O. After 20 minutes, followed him at the same speed the second cyclist. Walker, which went from O to N, started at 5:40. After 56 minutes he met the first cyclist and after next 16 minutes the second cyclist. D
  20. Triangle TBC
    isosceles_triangle TBC is isosceles triangle with base TB with base angle 52° and legs length |TC| = |BC| = 30. How long is the base TB?

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