Grade - examples - page 149

  1. Unknown number 4
    ninth I think number. When I divided its square root by its 1/9, I get a number 1. What number am I thinking?
  2. Cheetah
    gepard_1 Cheetah elapse 150 m for 5 seconds, the eagle reaches speeds up to 230 km/h, dolphin swims 1.2 km per minute. Which animal is the fastest and slowest? The results write as meters per second (m/s).
  3. Surface of cuboid
    kvader11_9 Find the surface of the cuboid if its volume is 52.8 cm3 and the length of its two edges is 2 cm and 6 cm.
  4. BTC bubble
    btc_2 One of the world's experts in bubbles -- Prof. Robert Shiller, a Yale economist -- said Bitcoin "was an amazing example of a bubble" back in 2014. If you exchange fiat US dollar $100 to BTC in 2010, now in 2017 have value of 72.9 millions dollars. Find.
  5. Workers
    okno2_1 Group of workers washing half of the windows of the building in two hours. How long will take half the workers wash all the windows of the building?
  6. Alcohol
    metaxa How many cubic centimeters of 96% alcohol is needed to obtain 0.75 liter of 40% alcohol?
  7. AP - simple
    sigma_1 Determine the first nine elements of sequence if a10 = -1 and d = 4
  8. Backpack
    batoh_1 Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks?
  9. Bicycle
    cestny_bicyk The bicycle pedal gear has 36 teeth, the rear gear wheel has 10 teeth. How many times turns rear wheel, when pedal wheel turns 120x?
  10. Rectangle
    rectangles_11 Find the dimensions of the rectangle, whose perimeter is 108 cm and the length is 25% larger than the width.
  11. Outer contact of circles
    nakres_2z Construct a circle k1 (S1; 1.5 cm), k2 (S2; 2 cm), and K3 (S3; 2.5 cm) so that they are always two outer contact. Calculate the perimeter of the triangle S1S2S3.
  12. Sheet of paper
    cubes2_3 Is the sheet of paper measuring 18 and 25 cm enough for taping 9 cm cubes with an edge? (1 = yes, 0 = no)
  13. Three monks
    Bible Three medieval monks has task to copy 600 pages of the Bible. One rewrites in three days 1 page, second in 2 days 3 pages and a third in 4 days 2 sides. Calculate for how many days and what day the monks will have copied whole Bible when they begin Wednesd
  14. Ladder
    rebrik_3 Ladder 10 meters long is staying against the wall so that its bottom edge is 6 meters away from the wall. What height reaches ladder?
  15. Sale off
    percents2_1 Product cost 95 euros before sale off. After sale off cost 74 euros and 10 cents. About what percentage of produt became cheaper?
  16. Trees
    tree_1 A certain species of tree grows an average of 0.5 cm per week. Write an equation for the sequence that represents the weekly height of this tree in centimeters if the measurements begin when the tree is 200 centimeters tall.
  17. Cylinder horizontally
    CylindricalSegment_1000 The cylinder with a diameter of 3 m and a height/length of 15 m is laid horizontally. Water is poured into it, reaching a height of 60 cm below the axis of the cylinder. How many hectoliters of water is in the cylinder?
  18. Tram lines
    elektricka_2 Trams of five lines driven at intervals of 5,8,10,12 and 15 minutes. At 12 o'clock come out of the station at the same time. About how many hours again all meet? How many times have earch tram pass for this stop?
  19. Land areas
    land Two land areas is 244 m2. The first parcel is 40 m2 less than twice of the second one. What have acreage of each parcel?
  20. Rectangle
    obdlznik The length of the rectangle is 12 cm greater than 3 times its width. What dimensions and area this rectangle has if ts circumference is 104 cm.

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