Examples for 8th grade - page 61

  1. Is right?
    RightTriangleSquares Determine whether the triangle with cathetuses 19.5 cm and 26 cm and length of the hypotenuse 32.5 cm is rectangular?
  2. Cube wall
    cube_shield_2 The perimeter of one cube wall is 120 meters. Calculate the surface area and the body diagonal of this cube.
  3. Two looms
    stav On two different looms with different performance can be make required quantity of textile in 6 hours when both work together. On the first machine this quantity of the textile can make in 10 hours. How long should take make same quantity of textile on a s
  4. Salt
    salt_4 Sea water containing 5% salt. How many kg of fresh water necessary to pour into 40 kg of sea water so that the salinity fell to 2%?
  5. Plan scale
    geodet At what scale is drawn plan of the building, where one side of the building is 45 meters long is on the plan expressed by a straight line 12 mm long.
  6. Journey to grandma
    moto_1 Daniel traveled to grandma. He travel 100 km along. Halfway travel by train, one quarter by bus, one tenth by the bicycle and the rest travel by car. How many km travel km by car?
  7. Percentages
    percent2 Expressed as a percentage:
  8. Minute
    compass Two boys started from one place. First went north at velocity 3 m/s and the second to the east with velocity 4 m/s. How far apart they are after minute?
  9. Driving school
    bmw-autoskola Driving final exam involving 10 attendants. The exam consists of three parts. 2 fails at test (quiz) and 6 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
  10. Proof I
    ithinkiam When added to the product of two consecutive integers larger one, we get square larger one. Is this true or not?
  11. Percentage reduction
    sales_percentages Reducing the unknown number by 19% get number 700.7 Determine unknown number.
  12. Circle and rectangle
    described_circle A rectangle with sides of 11.7 cm and 175 mm is described by circle. What is its length? Calculate the content area of the circle described by this circle.
  13. 3 years
    ekonomicky-rast The company has increased the number of employees. In year 2005 compared to 2004 13% more, in 2006 18% more against the previous year, in year 2007 20% more compared to 2006. How many % increase in the number of employees in 3 years?
  14. Rectangle from string
    obdelnik String 12m. Make rectangle when one side is two times longer than its width.
  15. Lift
    lanovka_2 The largest angle at which the lift rises is 16°31'. Give climb angle in permille.
  16. Candies
    bonbons_10 There are two types of candies in the store at 20 CZK/kg and 80 CZK/kg. How much will be cost a mix if we mix 22kg cheaper and 4kg more expensive candies?
  17. Ethnicity
    indian Share of ethnicity XY is 26%, which is 1/9 more than in the prewar period. What was the share of that ethnicity in the pre-war period?
  18. Sisters
    sestry20091 Sisters Janka and Danka are saved together 220 CZK. On a trip to Janka wants to take a fifth of her savings and Danka quarter. Then they will have 50 CZK on the trip. How much money saved Janka and Danka?
  19. Goods
    money To the market is introducing a new product, the first week is sold at a reduced price. 8 products is sell at an entry price same as 5 products at the normal price. How much % is reduced price less than the current price for this product?
  20. Triangular prism
    prism3 Calculate the volume and surface of the triangular prism ABCDEF with base of a isosceles triangle. Base's height is 16 cm, leg 10 cm, base height vc = 6 cm. The prism height is 9 cm.

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