Grade - examples - page 61

  1. Garden
    plot_1 Rectangular garden has a length 82 m and width 32 m. Calculate how many m2 will decrease its area if land by ornamental fence with width 50 cm.
  2. Permill
    permille How many permill is 978 from 84370?
  3. Integers
    calculator_mechanical May be the sum of two integers less than their difference?
  4. Sphere fall
    sphere How many percent fall volume of sphere if diameter fall 10×?
  5. Disinfecting solution
    desinfect How much distilled water is necessary to pour into 500 ml of 33% hydrogen peroxide solution to obtain 3% disinfecting solution?
  6. Diagonal
    rhombus Can a rhombus have the same length diagonal and side?
  7. Pipeline
    pipeline How much percent has changed (reduced) area of pipe cross-section, if circular shape changed to square with same perimeter?
  8. Ray
    luc-slnka Light ray loses 1/19 of brightness passing through glass plate. What is the brightness of the ray after passing through 7 identical plates?
  9. Soup
    kotlik On Monday we cook 25 pots and 10 boilers of soup. On Tuesday 15 pots and 13 boilers. On Wednesday 20 pots and on Thursday 30 boilers. On Monday and Tuesday was cooked the same amount of soup. How many times more soup cooked on Thursday than on Wednesday?
  10. Train 2
    zssk_vlak The train slowed down from 90 km/h to 72 km/h in 5 seconds. How long track travel?
  11. Cosine
    theta Calculate the cosine of the smallest internal angle in a right-angled triangle with cathetus 3 and 8 and with the hypotenuse 8.544.
  12. Circles
    circles How many different circles is determined by 9 points at the plane, if 6 of them lie in a straight line?
  13. Electrics - conductor
    wire_2 The wire is 106 meters long at 0 °C and at every temperature increase of 1 °C the length increases by 0.15 mm per 1 m length of wire. Determine a function which represents the overall length of the wire as a function of temperature. What is the length of t
  14. Cylinder - h2
    valec_1 Cylinder volume is 2.6 liters. Base area is 1.3 dm2. Calculate the height of the cylinder.
  15. Pedestrian and the cyclist
    cyklista_1 Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
  16. Digits
    numbers_2 Write the smallest and largest 1-digit number.
  17. Triangular pyramid
    trojboky_ihlan Determine the volume and surface area of a regular triangular pyramid having a base edge a=20 cm and a lateral edge b = 35 cm
  18. Glasses
    class Imagine a set of students in your class (number of students: 19), who wears glasses. How much minimum and maximum element may contain this set.
  19. Unknown number
    iks-icon Samuel wrote unknown number. Then he had add 200000 to the number and the result multiply by three. When it calculated he was surprised, because the result would have received anyway, if write digit to the end of original number. Find unknown number.
  20. Square
    squares_4 If we increase one side of square by its one-half then square perimeter increase by 10 cm. What is the side of the square?

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