Examples for 9th grade - page 12

  1. Parquet floor
    Parkett Three workers laid parquet floor for 2.9 hour. The first one would do this work alone 9 hours, the second in 7 hours. For how many hours would fulfill this work the third worker, if he worked alone?
  2. Radius
    green_circle Determine the radius of the circle, if its perimeter and area is the same number.
  3. Cu wire
    medeny-drat Copper wire has a length l = 980 m and diameter d = 8 mm. Calculate the weight if density of copper is ρ = 8500 kg/m3. Result round to one decimal place.
  4. Discount
    sales_discount Product has been discounted twice by 19%. What is the total discount given?
  5. Seedcake
    pletenky Seedcake costs 44 cents. How many minimum seedcakes we must buy that we can pay in cash only whole euros?
  6. 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 2 hours. How many hours will spend washing the windows this "women's team" if working togethe
  7. 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)
  8. Euclid1
    pravitko Right triangle has hypotenuse c = 27 cm. How large sections cuts height hc=3 cm on the hypotenuse c?
  9. Cuboid
    cuboid_diagonal Determine the dimensions of cuboid a, b, c; if diagonal d=9 dm has angle with edge a α=55° and has angle with edge b β=58°
  10. 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.
  11. Cubes
    rubik_cube Cube, which consists of 27 small cubes with edge 4 dm has volume:
  12. Freedom
    family_life In the city are 3/9 of women married for 3/6 men. What proportion of the townspeople is free (not married)? Express as a decimal number.
  13. 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?
  14. Map
    cycle_map On the tourist map at a scale of 1 : 50000 is distance between two points along a straight road 3.7 cm. How long travels this distance on a bike at 30 km/h? Time express in minutes.
  15. Clocks
    clocks How long path will walk the end of the clock's minute-hand long 7 cm for 330 minutes? How long will walk in the same time hour-hand?
  16. Square diagonal
    square_diagonal Calculate the length of diagonal of the square with side a = 4 cm.
  17. Triangle ABC
    ABC Right triangle ABC with right angle at the C, |BC|=18, |AB|=33. Calculate the height of the triangle hAB to the side AB.
  18. Building
    Taipei_101 How high is the building that throws horizontal shadow 95.4 m long at angle 50°?
  19. 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.
  20. Trains
    trains_toys From station 130 km away started passenger train and after 2.2 hours after the express train, which travels 37 km an hour more. Express train finish journey 7 minutes early. Calculate the average speed of this two trains.

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