Examples for 9th grade

  1. Building
    Taipei_101 How high is the building that throws horizontal shadow 95.4 m long at angle 50°?
  2. Triangle ABC
    triangles_3 Calculate the sides of triangle ABC with area 1404 cm2 and if a: b: c = 12:7:18
  3. Arc
    angles Convert to arc measures (radians): 924 ° Result write as a multiple of π
  4. River
    river From the observatory 11 m high and 24 m from the river bank, river width appears in the visual angle φ = 13°. Calculate width of the river.
  5. Equilateral triangle
    3angle_in_circle How long should be the minimum radius of the circular plate to be cut equilateral triangle with side 19 cm from it?
  6. Team
    football The football team has 11 players. Their average age is 20 years. During the match due to injury, one player withdraws and the average age of the team is 18. How old was injured player?
  7. Logs
    gulatina Trunk diameter is 52 cm. Is it possible to inscribe a square prism with side 36 cm?
  8. Lathe
    soustruh From the cube of edge 37 cm was lathed maximum cylinder. What percentage of the cube is left as waste after lathed?
  9. Percentages above 100%
    cmelak What is 122% of 185? What is the meaning of percentages above 100%?
  10. Rectangle
    rectangle_inscribed_circle The rectangle is 21 cm long and 38 cm wide. Determine the radius of the circle circumscribing rectangle.
  11. Two cars
    cars_racing Two cars started against each other at the same time to journey long 346 km. The first car went 53 km/h and the second 53 km/h. What distance will be between these cars 20 minutes before meet?
  12. Triangle in circle
    triangle_in_circle Vertices of the triangle ABC lies on a circle with radius 3 so that it is divided into three parts in the ratio 4:4:4. Calculate the circumference of the triangle ABC.
  13. Quadrant
    quadrants In what quadrant is a -1165° angle?
  14. Perpendicular
    perpendicular Determine the slope of the line perpendicular to the line p: y = -x +4.
  15. Components
    components In the box are 8 white, 4 blue and 2 red components. What is the probability that we pull one white, one blue and one red component without returning?
  16. Truck
    truck Truck went for 4 hours and 30 minutes. If truck increase speed by 11 km/h, went same distance in 2 hours. Calculate this distance.
  17. Sequence
    Quadratic_equation In the arithmetic sequence is given: Sn=2304, d=2, an=95 Calculate a1 and n.
  18. Pairs
    pair At the table sit 10 people, 5 on one side and 5 on the other side. Among them are 3 pairs. Every pair wants to sit opposite each other. How many ways can they sit?
  19. Cube zoom
    krychle_1 How many percents do we increase the volume and surface of the cube if we magnify its edge by 38 %?
  20. Garden
    garden_1 Area of a square garden is 6/4 of triangle garden with sides 56 m, 35 m, and 35 m. How many meters of fencing need to fence a square garden?

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