Examples for 8th grade - page 16

  1. Stock market
    money_1 Simon one day decided to invest € 69000 to the stock market. After six months he invested July 19 stock markets fell by 55%. Fortunately for Simon from July 19 5 to October 19 his shares have risen by 19%. Simon is then: ?
  2. Tea blend
    teas Tea blends are maked from two kinds of tea. In standard tea mixture are two teas in the ratio 1:3 and 40 g costs 42 CZK. In the premium tea mixture are weighing two teas in the ratio 1:1 and 50 grams costs 60 CZK. How much cost 10 grams of more expensive k
  3. Cylinder - A&V
    cylinder The cylinder has a volume 1287. The base has a radius 10. What is the area of surface of the cylinder?
  4. Sugar - cuboid
    kocky_cukor Pejko received from his master cuboid composed of identical sugar cubes with count between 1000 and 2000. The Pejko eat sugar cubes in layers. The first day eat one layer from the front, second day one layer from right, the third day one layer above. Yet i
  5. Posters
    posters Column with posters in the form of a cylinder is 2.4 m high and its diameter is 2.5 m. What is the content area for which it is possible to stick posters?
  6. KLMN
    trapezium In the trapezoid KLMN is given this informations: 1. segments KL and MN are parallel 2. segments KL and KM has same length 3. segments KN, NM and ML has same length. Determine the size of the angle KMN.
  7. Trains
    trains On double track line between stations K and M went against each other two trains. The first train passed the distance between stations for 3.5 hours, the second, which had an average speed of 12 km/h more passed for 3.05 hours. Calculate the distance betw
  8. Wood in the forest
    drevo The amount of wood in the forest was estimated at 7000 m3. How much wood will be in forest after 2 years if the annual growth of wood is 2.2% each year and logging 70 m3 each year?
  9. Greek railwayman
    greecerails_1 Wesley works for the Slovak railways since 1986. His salary is 864 €. His colleague, Evgenias works in the Greek State Railways from 1991. Earns 5010 € per month. Calculate how many hours a day must Evgenias work to earn as much as Wesley and if they w
  10. Barrel 3
    sud-s-vodou Barrel with water has a weight 118 kg. When we get off 75% of water it has a weight 35 kg. How many kg has empty barrel?
  11. n-gon
    x-gon What is the side length of the regular 5-gon inscribed in a circle of radius 12 cm?
  12. Free fall
    volny_pad Lloyd fall from height 7 m. Calculate the speed he hit the ground when falling with acceleration g = 9.81 m/s2
  13. Reservoir + water
    cuboid_water Reservoir completely filled with water weighs 12 kg. After pouring off three quarters of the amount of water weights 3 kg. Calculate the weight and volume of the reservoir.
  14. Cylinder - h
    cylinder_2 Cylinder volume is 215 cm3. Base radius is 2 cm. Calculate the height of the cylinder.
  15. Height
    thales_law Is right that in any right triangle height is less or equal half of the hypotenuse?
  16. Playing cards
    playing_cards How many possible ways are to shuffle 7 playing cards?
  17. Hexagon - MO
    6uholnik_nepravidelny The picture shows the ABCD square, the EFGD square and the HIJD rectangle. Points J and G lie on the side CD and is true |DJ|
  18. Right triangle
    right_triangles Calculate the missing side b and interior angles, perimeter and area of ​​a right triangle if a=10 cm and hypotenuse c = 16 cm.
  19. Moving
    movie Vojta left the house at three o'clockat 4 km/h. After half hour later went from the same place Filip by bicycle at speed 18 km/h. How long take Tilip to catch up Vojta and how far from the house?
  20. Lead cube
    pb_cube Calculate the edge of the cube made ​​from lead, which weighs 19 kg. The density of lead is 11341 kg/m3.

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