Examples for 9th grade

  1. Nitrogen
    playground One bag of urea containing 46 percent nitrogen weighs 25 kg. How many bags have to be purchased for fertilizing a field of 41003 square meters if the nitrogen dose is 50.0 kg per hectare?
  2. 3/8 off
    sale_2 A shirt cost 38.95 How much will you pay for the shirt if it has a discount tag for 3/8 off? Round to the nearest cent
  3. Two chords
    twochords In a circle with radius r = 26 cm two parallel chords are drawn. One chord has a length t1 = 48 cm and the second has a length t2 = 20 cm, with the center lying between them. Calculate the distance of two chords.
  4. Rectangular base pyramid
    jehlan_4b_obdelnik Calculate an area of the shell of the pyramid with a rectangular base of 2.8 m and 1.4 m and height 2.5 meters.
  5. Wall height
    hexa_pyramid Calculate the height of a regular hexagonal pyramid with a base edge of 5 cm and a wall height w = 20 cm.
  6. Triangular prism
    prism3 Calculate the surface of a triangular prism with the base of an equilateral triangle with a side length of 7.5 cm and a corresponding height of 6.5 cm. Prism height is 15cm.
  7. Hexa pyramid
    hexa_pyramid_1 The base of the regular pyramid is a hexagon, which can be described by a circle with a radius of 1 m. Find the volume of the pyramid 2.5 m high.
  8. Divide
    hrusky How many different ways can three people divide 7 pears and 5 apples?
  9. Two accounts
    bankovka Two accounts in the bank, one per year interest 2%, the second 3%. Total interest income 1900 USD. If interest rates were reversed, the yield would be USD 200 higher. What are the amounts on each account?
  10. Buttons
    oblek Men's shirt has sewn 9 buttons and blouse 3 buttons. Together they sewed 60 pieces and consumed 390 buttons. How many shirts?
  11. The fastest
    ship The fastest boat can reach speeds more than 710% as fast as the Queen Mary 2. How would you express this number as a fraction and as a decimal?
  12. The ball
    sphere4 The ball has a radius of 2m. What percentage of the surface and volume is another sphere whose radius is 20% larger?
  13. Squares above sides
    pataVysky Two squares are constructed on two sides of the ABC triangle. The square area above the BC side is 25 cm2. The height vc to the side AB is 3 cm long. The heel P of height vc divides the AB side in a 2: 1 ratio. The AC side is longer than the BC side. Calc
  14. Same force
    wood The trunk of 5m length and 95 kilograms has a center of gravity 2m from the thicker end. The tribe is carried by two men, one at the thicker end. At what distance does the trunk carry a man from the other end to make the same force on it?
  15. Rotaty motion
    rotaryMotion What is the minimum speed and frequency that we need to rotate with water can in a vertical plane along a circle with a radius of 70 cm to prevent water from spilling?
  16. TV competition
    test_1 In the competition, 10 contestants answer five questions, one question per round. Anyone who answers correctly will receive as many points as the number of competitors answered incorrectly in that round. One of the contestants after the contest said: We
  17. Newtonmeters
    kluc-skrutky The driver loosened the nut on the car wheel with a wrench that held 20 cm from the axis of the bolt. He acted on the key with a force of 320N. At what moment did he act on the bolt?
  18. Possible combinations - word
    dices2 How many ways can the letters F, A, I, R be arranged?
  19. Conical bottle
    cone-upside When a conical bottle rests on its flat base, the water in the bottle is 8 cm from it vertex. When the same conical bottle is turned upside down, the water level is 2 cm from its base. What is the height of the bottle?
  20. Two bodies
    cylinders The rectangle with dimensions 8 cm and 4 cm is rotated 360º first around the longer side to form the first body. Then, we similarly rotate the rectangle around the shorter side b to form a second body. Determine the ratio of surfaces of the first and seco

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