Examples for 9th grade - page 30

  1. Combi-triangle
    komb_triangle On each side of the square is marked 2 different points outside the vertices of the square. How many triangles can be constructed from this set of points, where each vertex of the triangle lie on the other side of the square?
  2. Car
    city The driver of a car is to get to 378 km distant city. From atlas found that 99 km will have to pass through the cities at average speed 48 km/h. Remainder of the journey pass outside the cities at average speed 117 km/h. Calculate how many hours it will ta
  3. Rectangle - sides
    colored_squares What is the perimeter of a rectangle with area 1026 cm2 if length of the shorter side is 11 cm shorter than the length of the longer side?
  4. Roller
    cestnyvalec Roller has a diameter of 0.97 m and a width 169 cm. How many m2 of road level when he turns 68-times?
  5. Driving school
    bmw-autoskola Driving final exam involving 17 attendants. The exam consists of three parts. 4 fails at test (quiz) and 3 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
  6. Maple
    tree_javor Maple peak is visible from a distance 4 m from the trunk from a height of 1.7 m at angle 50°. Determine the height of the maple.
  7. n-gon
    x-gon What is the side length of the regular 5-gon inscribed in a circle of radius 11 cm?
  8. Monty Hall
    Monty_open_door Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. W
  9. Free fall
    volny_pad Stephen fall from height 5 m. Calculate the speed he hit the ground when falling with acceleration g = 9.81 m/s2
  10. Euler problem
    euler Someone buys a 720 tolars towels. If it was for the same money of 6 more towels, it would be 6 tolars cheaper each. How many were towels?
  11. Circle and angle
    arc What is the length of the arc of a circle with radius r = 138 cm with cental angle 2.07 rad?
  12. Cube - angles
    cube_diagonal_1 Calculate angle between the wall diagonal and cube base. Calculate the angle between the cube body diagonal and cube base.
  13. Right triangle Alef
    r_triangle The perimeter of a right triangle is 132 cm, the hypotenuse is 55 cm long. Determine the lengths of the legs.
  14. Cancer
    cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
  15. Triangular prism
    hranol_3 Base of perpendicular triangular prism is a right triangle with leg length 5 cm. Content area of the largest side wall of its surface is 130 cm² and the height of the body is 10 cm. Calculate its volume.
  16. Age ratios
    age_1 The ratio of the age of the mother and daughter is 5:2 and after seven years the ratio will be 2:1.Before how many years was born the daughter?
  17. Percent
    percentage_2 Calculate how many % is the number 26.25 less than the number 105.
  18. AP - simple
    sigma_1 Determine the first nine elements of sequence if a10 = -1 and d = 4
  19. Welders
    svarec Welder do the job for six hours, the second one for 8 hours. How long do the job third welder if all together can do job in 2 hours?
  20. Surface area 2
    cubes Calculate how many % reduce the surface area of the cube is we reduced length of each edge by 10%.

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