Grade - examples - page 108

  1. Rectangle from string
    obdelnik String 12m. Make rectangle when one side is two times longer than its width.
  2. Bonbons
    bonbons_6 Create a mixture of 50 kg of candy on price 700Kč. Candies has prices: 820Kč, 660Kč and 580Kč. Use cross rule.
  3. 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?
  4. Grass garden
    koseni Mr. Grass would itself be mowed garden for 5 hours. His son Michael could do it for 7 hours. They agreed that they wake up at 5 am and begins to mow together. Ms. Grass needs drive into town at 8.30. Michael says that at that time they're done with work..
  5. Ferris wheel
    ruske-kolo Ferris wheel reaches to 22 m tall and moves at the speed of 0.5m/s. During one drive wheel rotates three times. What is the total drive time?
  6. 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?
  7. Water reservoir
    nadrz_9 The water tank has a cuboid with edges a= 1 m, b=2 m , c = 1 m. Calculate how many centimeters of water level falls, if we fill fifteen 12 liters cans.
  8. Tmp workers
    profesiadays Three temporary workers cleaned 60 m of walkway in 5 hours. How many meters of the walkway cleared seven volunteers for eight hours?
  9. Angles by cosine law
    357_triangle Calculate the size of the angles of the triangle ABC, if it is given by: a = 3 cm; b = 5 cm; c = 7 cm (use the sine and cosine theorem).
  10. Percentages
    percent2 Expressed as a percentage:
  11. Surface area
    kvader11_6 Calculate the surface area of a four-sides 2-m high prism which base is a rectangle with sides 17 cm and 1.3 dm
  12. Combined interest
    bank2 Combined interest: Carol has deposited CZK 100,000 in the bank with an annual interest rate of 1.5%. The money was put into the account 5.5.2016 and withdraw them all before Christmas 20.12.2016. How much money did she withdraw?
  13. 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
  14. Roof 7
    pyramid_in_cube_1 The roof has the shape of a regular quadrangular pyramid with a base edge of 12 m and a height of 4 m. How many percent is folds and waste if in construction was consumed 181.4m2 of plate?
  15. Building
    kocky Lenka has 22 cubes for the construction of building comprising three cubes in height, the width of two cubes, and the length of four cubes. Is she able to build an building with these cubes?
  16. Train
    vlak_meskajuci The train passes part of the line for 95 minutes at speed 75 km/h. What speed would have to go in order to shorten the driving time of 20 minutes?
  17. The chord
    circles_4 Calculate a chord length which the distance from the center of the circle (S, 6 cm) equals 3 cm.
  18. Matches
    matches George poured out of the box matches and composing them triangles and no match was left. Then he tries squares, hexagons and octagons and no match was left. How many matches must be at least in the box?
  19. Proof I
    ithinkiam When added to the product of two consecutive integers larger one, we get square larger one. Is this true or not?
  20. Trinity
    trojka How many different triads can be selected from the group 38 students?

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