Examples for 8th grade - page 39

  1. Euler problem
    euler Someone buys a 720 tolars towels. If it was for the same money of 6 more towels, it would be 6 tolars cheaper each. How many were towels?
  2. Heron backlaw
    heron_math Calculate missing side in a triangle with sides 33 and 27 and area 118.3.
  3. Cylinder - basics
    cylinder Cylinder with base radius r = 37 cm and height h=74 cm. Calculate:
  4. Roses 2
    ruze Aunt Rose went to the flower shop to buy a bouquet with three roses. The flower shop had white, yellow and red roses. How many different flowers bouquet can a flower make for Aunt Rose create? Write all the bouquet options.
  5. Sugar cubes
    cukr_5 The glass has 600 ml of tea, which represents 80% of the volume of the glass. If you put twenty regular sugar cubes of 2 cm in the tea, how many ml of tea are poured?
  6. Coach
    hokej_4 Average age of 24 players and a coach of one team is 24 years. The average age of players without a coach is 23 years. How old is the coach?
  7. Cancer
    cancer Of the 80 people 50 people ill cancer. What percentage of people isn't ill?
  8. Linear system
    vahy_eq Solve this linear system (two linear equations with two unknowns): x+y =36 19x+22y=720
  9. Tiles
    100dlazdic How many tiles of 20 cm and 30 cm can build a square if we have a maximum 100 tiles?
  10. Percentage - fractions
    rubik About what percentage we must increase number 1/6 to get number 1/3?
  11. 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?
  12. Reducing number
    123 Reducing the an unknown number by 28.5% we get number 243.1. Determine unknown number.
  13. Aquarium 6
    water_aquarium How high is the water level in the aquarium with a rectangular base 40cm and 50cm if it is filled 0,65hl of water?
  14. Mom and daughter
    family_1 Mother is 39 years old. Her daughter is 15 years. For many years will mother be four times older than the daughter?
  15. angles in quadrilateral
    4uhelnik What size have angles in quadrilateral (4-gon) if they are in a ratio of 8: 9: 10: 13?
  16. Truck
    auto In 7 hours started from town Krnov truck at speed 40 km/h. Passenger car started against it in 8 hours 30 minutes from the city of Jihlava at speed 70 km/h. Distance between this two cities is 225 km. At what time and at what distance from Krnov this two.
  17. Salt
    sol 1 t of sea water contains 25 kg of salt. How many tons of seawater must be evaporated to obtain 2 q of salt?
  18. Coal
    coal If the daily consumption of 1.6 tons of coal, it is sufficient to supply the boiler for 42 days. How long is sufficient to supply when will burn only 1.2 tons of coal a day ?
  19. Tailor master
    saty There are less than 50m of textile in the tailoring workshop. When cutting on a blouse (consumption 1.5m), no textile is left. When using a cloth (consumption of 3.2m), no textile is left. How many meters of textile are in a tailor's workshop?
  20. Painters
    maliri 15 painters painted fence for 280 minutes. For how many minutes paint half of this fence 12 painters?

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