Latest problems - page 7

  1. Cubes into cuboid
    cubes_21 How many 12 centimeter cubes fit into the block (cuboid) with 6dm, 8,4dm and 4,8?
  2. Three pumps
    watertank_2 The water tank is emptied with the first pump in 6 hours, with the second pump in 2 hours. In order to be emptied in 1 hour, all three pumps had to be started at once. How long will take tank be emptied by only the third pump?
  3. Right angled triangle 3
    right_triangle_3 Side b = 1.5, hypotenuse angle A = 70 degrees, Angle B = 20 degrees
  4. Soaps
    mydlo_1 Each box has the same number of soaps. A quarter of all boxes contain only white soaps, and in each of the remaining 120 boxes there are always half the white soaps and half the green. White soaps total 1200. (a) the number of all soap boxes; (b) the sma
  5. Two equations
    children_23 Solve equations (use adding and subtracting of linear equations): -4x+11y=5 6x-11y=-5
  6. Three 43
    penize_49 Three brothers inherited a cash amount of 62,000 and they divided it among themselves in the ratio of 5:4:1. How much more is the largest share than the smallest share?
  7. Surface area 6
    prism3s Find the surface area of a prism whose bases are right triangles with sides of length 3, 4, and 5 inches and a height of 8 inches. Include a sketch
  8. Pizza 5
    pizza_8 You have 2/4 of a pizza and you want to share it equally between 2 people how much pizza does each person get?
  9. The room
    malovka_5 The room has a cuboid shape with dimensions: length 50m and width 60dm and height 300cm. Calculate how much this room will cost paint (floor is not painted) if the window and door area is 15% of the total area and 1m2 cost 15 euro.
  10. Body diagonal - cube
    cube_shield Calculate the surface and cube volume with body diagonal 15 cm long.
  11. Water lilies
    lekno_2 Water lilies are growing on the pond and their number is doubled every day. The whole layer is covered in 12 days. How many days will it cover 8 layers?
  12. Water flow 2
    water3_9 How many litres of water will flow in 7 minutes from a cylindrical pipe 1 cm in diameter, if the water flows at a speed of 30 km per hour
  13. Largest angle of the triangle
    obtuse_triangle Calculate the largest angle of the triangle whose sides have the sizes: 2a, 3/2a, 3a
  14. A bridge
    arc123 A bridge over a river is in the shape of the arc of a circle with each base of the bridge at the river's edge. At the center of the river, the bridge is 10 feet above the water. At 27 feet from the edge of the river, the bridge is 9 feet above the water. H
  15. Train speed
    trains_9 Two guns were fired from the same place at an interval of 10 minutes and 30 seconds, but a person in a train approaching the place hears second shot 10 minutes after the first. The speed of the train (in km/hr), supposing that sound travels at 340 m/s is:
  16. Rectangular prism
    kvader11_2 If i have a rectangular prism with a length of 1,000 cm, width of 30 cm and a height of 50 cm, what is the volume?
  17. Mysterious number
    fun3_9 The magician thinks the number: "The mysterious number is first divided by minus five, dividing the result by three, multiplying the number by ten, and dividing the resulting number by minus four. This gives result 5. Can you reveal the mysterious number?
  18. Thunderstorm
    storm-012_1 The sound travels 1 km in about 3 seconds. How far is the storm if there is a time interval of 8 seconds between lightning and thunder?
  19. Rain
    rain_8 It rains at night. On 1 m2 of lake will drop 60 liters of water. How many cm will the lake level rise?
  20. Average age
    candles_1 The company of five people has an average age of 46 years. The average age of the first four is 43 years. How many years has the fifth member of this company?

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