Units - examples

  1. Cube into sphere
    sphere_in_cylinder_1 The cube has brushed a sphere as large as possible. Determine how much percent was the waste.
  2. CuSO4 mixture
    chemia_2 How many grams of solid CuSO4 we have to add to 450g of 15% CuSO4 solution to produce a 25% solution?
  3. Sum of inner angles
    angle-sum-of-polygon Prove that the sum of all inner angles of any convex n-angle equals (n-2) . 180 degrees.
  4. The big clock
    hodiny_4 The big clock hands stopped at a random moment. What is the probability that: a) a small hand showed the time between 1:00 and 3:00? b) the big hand was in the same area as a small hand in the role of a)? c) did the hours just show the time between 21:00.
  5. Sandbox
    sand_2 Sandbox has area of 32 sq ft and length of 4 1/2 ft. What is width of sandbox.
  6. Length subtracting
    meter_11 Express in mm: 5 3/10 cm - 2/5 mm
  7. Performance
    workers_42 Two masons with the same performance would have made of plaster for 6 days. One of them, however, has increased its daily performance by 50%. How long would take they now to make plaster together?
  8. The perimeter
    hexagon6 The perimeter of equilateral △PQR is 12. The perimeter of regular hexagon STUVWX is also 12. What is the ratio of the area of △PQR to the area of STUVWX?
  9. Bulbs
    bulbs_2 There are 875 identical light bulbs in the sports hall lightning for 2 hours. How long does it lightning 100 this light bulbs?
  10. 40% volume
    workers_41 40% volume with 104 uph (units per labor hour) 8 people working. What is the volume?
  11. Scientific notation
    scientific Approximately 7.5x105 gallons of water flow over a waterfall each second. There are 8.6x104 seconds in 1 day. Select the approximate number of gallons of water that flow over the waterfall in 1 day.
  12. Equilateral cylinder
    sphere_in_cylinder A sphere is inserted into the rotating equilateral cylinder (touching the bases and the shell). Prove that the cylinder has both a volume and a surface half larger than an inscribed sphere.
  13. An oil
    valec2_13 An oil drum is cut in half. One half is used as a water trough. Use the dimensions; length 82cm, width 56cm to estimate the capacity of the water trough in liters.
  14. Third of an hour
    clocks2_18 How many minutes is a third of an hour? Do you know to determine a third of the lesson hour (45min)?
  15. Resistance
    Rezistor_2 A resistor having an electrical resistance of 1.5 k ohms passes an electrical current of 0.1 A. Calculate what voltage is between the terminals of the resistor.
  16. If the
    tan If the tangent of an angle of a right angled triangle is 0.8. Then its longest side is. .. .
  17. In a 2
    angles_7 In a thirteen sided polygon, the sum of five angles is 1274°, four of the eight angles remaining are equal and the other four are 18° less than each of the equal angles. Find the angles. .
  18. Six-sided polygon
    hexagon-irregular In a six-sided polygon. The first two angles are equal, the third angle is twice (the equal angles), two other angles are trice the equal angle, while the last angle is a right angle. Find the value of each angle.
  19. Area of iso-trap
    diagons-of-an-isosceles-trapezoid Find the area of an isosceles trapezoid, if the lengths of its bases are 16 cm, and 30 cm, and the diagonals are perpendicular to each other.
  20. 3 cats
    mouse_1 3 cats eat 3 mice in 3 days. How many mice will eat 10 cats in 10 days?

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