Examples for 8th grade - page 89

  1. Regular n-gon
    10gon_polygon In a regular n-angle polygon the internal angle is 144 degrees. Find the number n indicating the number of sides of this polygon.
  2. Sugar 9
    cukr_6 150 kg of sugar beet yields 24 kg of sugar. From how many tons of sugar beet can be obtained three tons of sugar?
  3. Shots
    lopta_5 Determine the percentage rate of keeper interventions if from 32 shots doesn't caught four shots.
  4. Is right triangle
    triangle_1111_4 Decide if the triangle XYZ is rectangular: x = 4 m, y = 6 m, z = 4 m
  5. Diagonals
    koso_uhlopricky Given a rhombus ABCD with a diagonalsl length of 8 cm and 12 cm. Calculate the side length and content of the rhombus.
  6. Hexagon area
    hexagon_1 The center of the regular hexagon is 21 cm away from its side. Calculate the hexagon side and its area.
  7. Forces on earth directions
    compass2_1 A force of 60 N [North] and 80 N [East] is exerted on an object wigth 10 kg. What is the acceleration of the object?
  8. Ladder
    rebrik_2 The ladder has a length 3.5 meters. He is leaning against the wall so that his bottom end is 2 meters away from the wall. Determine the height of the ladder.
  9. Adam and Ben
    venn_diagram_3_2 When Ben is so many years old to Adam today, Adam will be 23 years old. When Adam was as old as Ben, Ben was two years old. How old is today Ben and Adam?
  10. Quadrangular prism
    hranol4sreg_7 Calculate the volume and surface area of a regular quadrangular prism 35 cm high and the base diagonal of 22 cm.
  11. VAT on books
    books_13 The cost of a book in the store is 12.5 euros. How much euros is the VAT of this book? VAT is 10%.
  12. Two lands
    pozemky The common area of the two neighboring lands is 964 m2. The second land is 77 m2 smaller than twice the size of the first land. Find the areas of each land.
  13. Volume and area
    cubes_8 What is the volume of a cube which has area of 361 cm2?
  14. The cellar
    X Mr Novák has a cellar and a cellar window in the chalet has 0.6 meter square window. The window wishes to place an X-shaped grid in a square. He uses iron welded bars. Calculate the lengths of individual bars and what the total length of the bars he has t
  15. Cooling liquid
    chladici Cooling liquid is diluted with water in a ratio of 3:2 (3 parts by volume of coolant with 2 volumes of water). How many volumes of coolant must be prepared for a total 0.7 dm3 (liters) of the mixture?
  16. Trapezium
    trapezium_1 The area of trapezium is 35 cm2. Find its altitude if the bases are 6cm and 8 cm.
  17. Proportion
    proportion write the following proportion 8 is to 64 as to 2 is to x
  18. Frameworks is bad
    space Calculate how many percent will increase the length of an HTML document, if any ASCII character unnecessarily encoded as hexadecimal HTML entity composed of six characters (ampersand, grid #, x, two hex digits and the semicolon). Ie. space as:  
  19. Two boats
    ship_2 The sightseeing boat sail at 25 km / h. The cruise take 6 hours. How long the another boat sails at 60 km/h?
  20. Kaufland sales-off
    kaufland As a rule the goods to the approaching end consumption in Kaufland three days before the end of the consumption to 30% off and one day before the end of the consumption to 50% discounts. Sometimes however the seller has been mistaken and the second discoun

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