Examples for 8th grade - page 65

  1. Sinus
    sine_cosine Determine the smallest integer p for which the equation 4 sin x = p has no solution.
  2. Cube 6
    water_cube Surface area of one wall cube is 1600 cm square. How many liters of water can fit into the cube?
  3. Coffee shop
    coffee-beans To the coffee shop brought 2 types of coffee totally 50 kg. The first type was CZK 220 per kilogram, coffee second type 300 CZK per 1 kg. For all the coffee trader earned CZK 12,000. How many kilograms of coffee of first type and how many kilograms of cof
  4. Square garden
    garden_4 On the plan with a scale of 1:1500 is drawn as a square garden with area 81 cm2. How many meters is long garden fence? Determine the actual acreage gardens.
  5. Borrowed book
    TB Jane must as soon as possible return a borrowed book. She figured that when she read 15 pages a day return book in time. Then she read 18 pages a day and then return the book one day before. How many pages should have a book?
  6. Apprentice
    ucen Worker and apprentice execute the work for 6 hours. Worker performs himself in 10 hours. How long do the work of an apprentice?
  7. Cube diagonals
    krychlicka_1 Determine the volume and surface area of the cube if you know the length of the body diagonal u = 216 cm.
  8. Algebrogram
    plus_2 Solve algebrogram: mama+anna=vari How many solutions are?
  9. Grandmother
    cukriky_3 Grandmother wants to give the candies to grandchildren that when she gives 5 candy everyone 3 missing and when she gives 4 candies 3 is surplus. How many grandchildren has grandmother and how many candies has?
  10. Car
    sanitka_1 Car goes some distance in 3 hours and 20 minutes. If it increase speed by 10 km/h, i goes this distance in 2.5 hours. Calculate the distance.
  11. Painters 4
    painter_3 One painter will do the job for 12 days. After a 4 1/3 day he comes second to help him and complete work together for 8 days. How long would work the second painter himself?
  12. Tiles
    100dlazdic How many tiles of 20 cm and 30 cm can build a square if we have a maximum 100 tiles?
  13. Saving
    2kc Paul save 155Kč in 46 2 Kc and 5Kc coins. How much saved 2Kc and 5Kc coins?
  14. After 16 years
    diana After 16 years will Dana be five times older as she was four years ago. After how many years will Dana celebrate her 16th birthday?
  15. Cube 5
    cube_4 The surface of the cube is 15.36 dm2. How will change the surface area of this cube if the length of the edges is reduced by 2 cm?
  16. Mushrooms
    mushrooms-01 For five days, we have collected 410 mushrooms. Interestingly every day we have collected 10 mushrooms more than the preceding day. How many mushrooms we have collected during 4th day?
  17. Sines
    sines In ▵ ABC, if sin(α)=0.5 and sin(β)=0.6 calculate sin(γ)
  18. Loan
    money_2 If you take a bank loan $ 10000 and we want to repay after the year, we have to pay the total amount $ 10320/ What is the annual interest rate on this loan?
  19. Three dice
    3_cubes When you throw three dice was the sum total of the dice 10. The yellow dice fell one eye more than on the red and brown fell 3 eyes less than red. How many eyes fell on every dice?
  20. Interst on savings
    ecb_2 The bank offers 1.6% interest. How many euros have to insert at the beginning if we received € 15 on the interest?

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