Examples for 8th grade - page 25

  1. Tank and water
    chemickelaboratorium1 Cylindrical tank were poured with 3.5 liters of water. If tank base diameter is 3 dm, how height is water level in?
  2. Hexagonal pyramid
    hexagonal-pyramid Base of the pyramid is a regular hexagon, which can be circumscribed in a circle with a radius of 1 meter. Calculate the volume of a pyramid 2.5 meters high.
  3. Prism - box
    cuboids_1 The base of prism is a rectangle with a side of 7.5 cm and 12.5 cm diagonal. The volume of the prism is V = 0.9 dm3. Calculate the surface of the prism.
  4. Hairs
    parochna Suppose the length of the hair is affected by only the α-keratin synthesis, which is the major component. This synthesis takes place in the epithelial cells of the hair bulb. The structure of α-keratin is made up of α-helix, wherein in one revolution it is
  5. Semicircle
    tales-de-mileto In the semicircle with center S and the diameter AB is constructed equilateral triangle SBC. What is the magnitude of the angle ∠SAC?
  6. Hockey players
    players After we cycle five hockey players sit down. What is the probability that the two best scorers of this crew will sit next to each other?
  7. Two valves
    pool_2 Water fill the pool by two valves for 11 days. After 7 days the first valve was stopped and the second valve fill pool for 7 days. How many days took to fill the pool each of the valves individually?
  8. Ladislav in Amsterdam
    jakob3 Ladislav was reward and went to conference in Amsterdam. Conferense fee was € 3484. Calculate how many books Ladislav could buy at the price of 48 and 52 euros if he don't want fill whole home library and he can buy only 70 books?
  9. Cone
    cones_1 If the segment of the line y = -3x +4 that lies in quadrant I is rotated about the y-axis, a cone is formed. What is the volume of the cone?
  10. Fixed expenses 2013
    istoty_komunisti Since 2013, the Slovak government plans to tax more small one person businesses. Instead of fixed expences 40% will be fixed expences 40% of gross income up to 420 Eur. Calculate what percentage of fixed expences will in 2013 pays from gross income 2236 E
  11. Segments
    abs Which of the pairs of numbers on the number line encloses the longest segment: ?
  12. Vertical prism
    hranoly3 The base of vertical prism is a right triangle with leg a = 5 cm and a hypotenuse c = 13 cm. The height of the prism is equal to the circumference of the base. Calculate the surface area and volume of the prism
  13. Mushrooms
    huby Fresh mushrooms contain 94% water, dried 14%. How many kg of fresh mushrooms is needed to collect to get 10 kg dried?
  14. Rhombus diagonal
    rhombus2_1 Area of rhombus is 224. One diagonal measures 33, find length of other diagonal.
  15. Elections
    elections The elections attended a total 4818 voters. First day 39 men more than women, the second day 21 women more than men. How many women attended elections?
  16. Triangle SAA
    triangle_blue The triangle has one side long 71 m and its two internal angles is 60°. Calculate the perimeter and area of the triangle.
  17. Leg
    tetris Determine the area of a trapezoid with bases 71 and 42 and height is 4 shorter than the its leg.
  18. Series
    posloupnost_an Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?
  19. Baker
    pekar The baker makes from 10 kg of flour 12 kg dough. How much flour he need to make a 100 kg dough?
  20. Snowman 2
    snowman_1 On the medal, which has the shape of a circle with a diameter 18 cm is sketched snowman so that the following requirements are met: 1. snowman is composed of three circles, 2. space over snowman is the same as under it, 3. diameters of all circles express

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