Examples for 8th grade - page 12

  1. Cuboid
    cuboid_diagonal Determine the dimensions of cuboid a, b, c; if diagonal d=6 dm has angle with edge a α=57° and has angle with edge b β=60°
  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. Building
    Taipei_101 How high is the building that throws horizontal shadow 58.5 m long at angle 36°36'?
  4. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 18 cm.
  5. Madams
    womans During the spring cleaning ladies going to wash windows. Mother takes wash all the windows 5 hours, the grandmother 3 times longer and Paula wash all windows in 5 hours. How many hours will spend washing the windows this "women's team" if working togethe
  6. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 3 dm has volume:
  7. Floating barrel
    floating_barrel Barrel (cylinder shape) floats on water, top of barrel is 7 dm above water and the width of surfaced barrel part is 20 dm. Barrel length is 27 dm. Calculate the volume of the barrel.
  8. Percent calculation
    percent_sign Calculate 72% if 96% is 93.
  9. 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)
  10. Garden
    garden_2 Father dig up the garden in 13 hours. Son in 18 hours. How many hours take dig up the garden together?
  11. Pool
    bazen Mr. Peter build a pool shape of a four-sided prism with rhombus base in the garden. Base edge length is 6 m, distance of the opposite walls of the pool is 5 m. Estimated depth is 193 cm. How many hectoliters of water consume Mr. Peter to fill the pool?
  12. 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.
  13. Estate
    semicircle Semicircle estate must be fence. The straight section has 44 meters long fence. How many meters of fence should buy?
  14. 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?
  15. Stairway
    steps What angle rising stairway if step height in 17 cm and width 24 cm?
  16. 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?
  17. Seedcake
    pletenky Seedcake costs 50 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  18. 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?
  19. Speed of Slovakian trains
    zssk_train Rudolf decided to take the train from the station 'Nová Baňa' to 'Gelnica'. In the train timetables found train R 371 Horehronec : km0Břeclav os.n.05:268Lanžhot05:3205:3214Brodské05:3705:3818Kúty05:4205:4344Malacky05:5906:0082Bratislava hl.st.06:2606:37
  20. 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.

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