Examples for 9th grade - page 11

  1. Euclid1
    pravitko Right triangle has hypotenuse c = 15 cm. How large sections cuts height hc=7 cm on the hypotenuse c?
  2. Clocks
    clocks How long path will walk the end of the clock's minute-hand long 24 cm for 110 minutes? How long will walk in the same time hour-hand?
  3. Seedcake
    pletenky Seedcake costs 50 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  4. Triangle ABC
    ABC Right triangle ABC with right angle at the C, |BC|=20, |AB|=35. Calculate the height of the triangle hAB to the side AB.
  5. Building
    Taipei_101 How high is the building that throws horizontal shadow 58.5 m long at angle 36°36'?
  6. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 18 cm.
  7. Freedom
    family_life In the city are 2/6 of women married for 4/4 men. What proportion of the townspeople is free (not married)? Express as a decimal number.
  8. Trains
    trains_toys From station 130 km away started passenger train and after 2.8 hours after the express train, which travels 24 km an hour more. Express train finish journey 14 minutes early. Calculate the average speed of this two trains.
  9. Phone numbers
    old_phone How many 9-digit telephone numbers can be compiled from the digits 0,1,2,..,8,9 that no digit is repeated?
  10. Wire
    cu_wire One pull of wire is reduced its diameter by 9%. What will be diameter of wire with diameter 9 mm over 8 pulls?
  11. n-gon II
    x-gon_1 What is the side length of the regular 9-gon circumscribed circle of radius 13 cm?
  12. Estate
    semicircle Semicircle estate must be fence. The straight section has 44 meters long fence. How many meters of fence should buy?
  13. Octahedron - sum
    8sten On each wall of a regular octahedron is written one of the numbers 1, 2, 3, 4, 5, 6, 7 and 8, wherein on different sides are different numbers. For each wall John make the sum of the numbers written of three adjacent walls. Thus got eight sums, which also.
  14. 4side pyramid
    ihlany Calculate the volume and surface of 4 side regular pyramid whose base edge is 4 cm long. The angle from the plane of the side wall and base plane is 60 degrees.
  15. Square 2
    square_ABCD_1 Points D[9,-1] and B[3,3] are opposed vertices of the square ABCD. Calculate area of the square ABCD.
  16. Stairway
    steps What angle rising stairway if step height in 17 cm and width 24 cm?
  17. Canopy
    cone-roof Mr Peter has metal roof cone shape with a height of 36 cm and radius 73 cm over well. He needs paint the roof with anticorrosion. How many kg of color must he buy if the manufacturer specifies the consumption of 1 kg to 2.1 m2?
  18. Prism
    prism_rhombus_1 Calculate the volume of the rhombic prism. Base of prism is rhombus whose one diagonal is 39 cm and the edge of the base is 24 cm. The edge length of the base of the prism and height is 3:2.
  19. Climb
    scenic_road Road has climbing 1:23. How big is a angle corresponds to this climbing?
  20. n-gon
    ngon_1 Gabo draw n-gon, which angles are consecutive members of an arithmetic sequence. The smallest angle is 70° biggest 170°. How many sides have Gabo's n-gon?

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