Examples for 8th grade - page 12

  1. 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?
  2. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 3 dm has volume:
  3. Building
    Taipei_101 How high is the building that throws horizontal shadow 58.5 m long at angle 36°36'?
  4. Diofant equation
    diofantos In the set of integers (Z) solve the equation: ? Write result with integer parameter ? (parameter t = ...-2,-1,0,1,2,3... if equation has infinitely many solutions)
  5. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 18 cm.
  6. 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.
  7. Seedcake
    pletenky Seedcake costs 50 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  8. Percent calculation
    percent_sign Calculate 72% if 96% is 93.
  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. Plumber
    klempir Plumber had to cut the metal strip with dimensions 380 cm and 60 cm to the largest squares so that no waste. Calculate the length of the sides of a square. How many squares cut it?
  11. Estate
    semicircle Semicircle estate must be fence. The straight section has 44 meters long fence. How many meters of fence should buy?
  12. 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?
  13. Parquet floor
    Parkett Three workers laid parquet floor for 1.957 hour. The first one would do this work alone 5 hours, the second in 9 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  14. Rhombus 2
    koso Calculate the area of rhombus which has a height v=48 mm and shorter diagonal u = 60 mm long.
  15. Road embankment
    nasyp_cesta Road embankment has a cross section shape of an isosceles trapezoid with bases 9 m and 12 m, and 4 m long leg. How many cubic meters of soil is in embankment length of 758 meters?
  16. Stairway
    steps What angle rising stairway if step height in 17 cm and width 24 cm?
  17. 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.
  18. Metallurgical enterprise
    iron_industry Metallurgical company daily produces 873 tons of cast iron. How many tons of coke it burns to melt cast iron when 17 tons of cast consumes 13 tons of coke?
  19. 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?
  20. 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.

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