Examples for 9th grade - page 88

  1. The coil
    lano_1 How many ropes (the diameter 8 mm) fit on the coil (threads are wrapped close together) The coil has dimension: the inner diameter 400mm, the outside diameter 800mm and the length of the coil is 470mm
  2. Triangles
    triangle_234 Five sticks with a length of 2,3,4,5,6 cm. How many ways can you choose three sticks to form three sides of a triangle?
  3. Big cube
    cubes_23 Calculate the surface of the cube, which is composed of 64 small cubes with an edge 1 cm long.
  4. Right triangle
    rt_A Calculate the length of the remaining two sides and the angles in the rectangular triangle ABC if a = 10 cm, angle alpha = 18°40'.
  5. Budget plan
    penize_49 In the construction of the building, the planned budget exceeded 13%, which was 32,500 euros. How many euros cost built the building?
  6. 7 digit number
    numbers2_49 If 3c54d10 is divisible by 330, what is the sum of c and d?
  7. Rectangles
    rectangle_15 The perimeter of a rectangle is 90 m. Divide it into three rectangles, the shorter side has all three rectangles the same, their longer sides are three consecutive natural numbers. What is the dimensions of each rectangle?
  8. The tank
    pipe2_4 The tank had 9 inflows to be filled in 21 days. After 9 days, 3 trips out. How many days did the remaining 6 tributaries fill the tank?
  9. Parking
    cars_27 At a building parking, 245 spaces are for cars, 56 are for vans and the rest are for buses. If 14% of all parking spaces are for buses, how many parking spaces are there in the building? How many spaces are for buses?
  10. Is right-angled
    rt_sqrt_2 Can a triangle with the sides of sqrt 3, sqrt 5 and sqrt 8 (√3, √5 a √8) be a right triangle?
  11. Cube diagonals
    cube_diagonals The cube has a wall area of 81 cm square. Calculate the length of its edge, wall, and body diagonal.
  12. Discount
    saty_1 The dress was discounted by CZK 115, which was 12% of the original price. What is the cost of the dress after the discount?
  13. Inscribed circle
    vpisana2 Calculate the magnitude of the BAC angle in the triangle ABC if you know that it is 3 times less than the angle BOC, where O is the center of the circle inscribed in the triangle ABC.
  14. Body diagonal
    diagonal_1 Calculate the length of the body diagonal of the 6cm cube.
  15. Area of garden
    garden_20 If the width of the rectangular garden is decreased by 2 meters and its length is increased by 5 meters, the area of the rectangle will be 0.2 ares larger. If the width and the length of the garden will increase by 3 meters, its original size will increas
  16. Car driver
    cars_26 The car driver is in town A and is scheduled to be in town B at a specified hour. If it travels at an average speed of 50km/h, it will arrive in city B 30 minutes later. But if he travels at an average speed of 70km/h, he would arrive half an hour earlier
  17. The train
    train_freight_6 The train passed the observer in the 20s and passed through a 1500m tunnel in 2 minutes. Calculate the speed (km/h) and train length.
  18. CuSO4 mixture
    chemia_2 How many grams of solid CuSO4 we have to add to 450g of 15% CuSO4 solution to produce a 25% solution?
  19. Cone 15
    cone_9 The radius of the base of a right circular cone is 14 inches and it's height 18 inches. What is the slant height?
  20. Christmas
    christmas_1 Father said: "exactly after 56 hours we will sit down to Christmas Eve table" How was and what time it was when Father said this sentence? The Christmas Eve table they sit down at exactly 6 PM hour.

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