Latest problems - page 2

  1. Geometric progression 4
    square_rot_1 8,4√2,4,2√2
  2. Algebra
    parabol_3 X+y=5, find xy (find the product of x and y if x+y = 5)
  3. 5 people
    penize_49 5 people have $122000 and 1 person has $539000 How much should each person (equally) pay?
  4. Length subtracting
    meter_11 Express in mm: 5 3/10 cm - 2/5 mm
  5. Simplify 3
    fractal_14 Simplify mixed numerals expression: 8 1/4- 3 2/5 - (2 1/3 - 1/4) Show your solution.
  6. Adding mixed numerals
    zlomky_18 3 3/4 + 2 3/5 + 5 1/2 Show your solution.
  7. Utopia Island
    doktori A probability of disease A on the island of Utopia is 40%. A probability of occurrence among the men of this island, which make up 60% of all the population (the rest are women), is 50%. What is the probability of occurrence of A disease among women on Uto
  8. 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?
  9. 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?
  10. 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?
  11. 75th percentile (quartille Q3)
    statistics Find 75th percentile for 30,42,42,46,46,46,50,50,54
  12. 40% volume
    workers_41 40% volume with 104 uph (units per labor hour) 8 people working. What is the volume?
  13. 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.
  14. 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.
  15. 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.
  16. 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)?
  17. 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.
  18. Cube edges
    cube_shield_3 The sum of the lengths of the cube edges is 42 cm. Calculate the surface of the cube.
  19. Hyperbola
    hyperbola Find the equation of hyperbola that passes through the point M [30; 24] and has focal points at F1 [0; 4 sqrt 6], F2 [0; -4 sqrt 6].
  20. Ellipse
    elipsa Ellipse is expressed by equation 9x2 + 25y2 - 54x - 100y - 44 = 0. Find the length of primary and secondary axes, eccentricity, and coordinates of the center of the ellipse.

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