Percentages + volume - math problems

  1. Kostka
    sphere_in_cube Kostka je vepsána do koule o poloměru r = 6 cm. Kolik procent tvoří objem kostky z objemu koule?
  2. Triangular prism
    hranol3b The base of the perpendicular triangular prism is a rectangular triangle with a hypotenuse of 10 cm and one leg of 8 cm. The prism height is 75% of the perimeter of the base. Calculate the volume and surface of the prism.
  3. Lemonade
    juice Iva added one liter of 100% fruit juice to 3 liters of water. She left two liters of it for Alice and Beata. She added two more liters of water to the remain two liters of lemonade and offered it to other friends. a. What percentage of juice did Alena an
  4. The ball
    sphere4 The ball has a radius of 2m. What percentage of the surface and volume is another sphere whose radius is 20% larger?
  5. Pouring alcohol
    roztoky 100 liters of alcohol has 70% How many liters of water need to be added to have 60% alcohol?
  6. Alcohol
    chemia 6l 48% alcohol, how much 52% alcohol must be added to give 50% alcohol?
  7. Water in vegetables
    rajciny Tomatoes in the store contain 99% water. After being transported to the shop, they were slightly dried and contained only 98% of water. How many kgs of tomatoes are in the store if there were 300 kg in stock?`
  8. Camel and water
    tava 84% of the camel's weight is water. After drinking, its weight increased to 832 kg and water accounted for 85% of its weight. How much did it weigh before drinking?
  9. Gasoline-oil ratio
    fuel-pump The manufacturer of a scooter engine recommends a gasoline-oil fuel mixture ratio of 15 to 1. In a particular garage, we can buy pure gasoline and a gasoline-oil mixture, which is 75% gasoline. How much gasoline and how much of the gasoline-oil mix do w
  10. Sphere radius
    SpheresDiff The radius of the sphere we reduce by 1/3 of the original radius. How much percent does the volume and surface of the sphere change?
  11. Lemonade
    limonada In January, 2 liters of lemonade were sold for CZK 24, while in February, 2.5 liters of lemonade sold at same price. How much percent was 1 liter of lemonade cheaper in February than in January?
  12. Clogging
    h2o2 How much distilled water must the pharmacist add to 30g of a 30% hydrogen peroxide solution to obtain a 3% solution to clogging?
  13. Winery
    wines_2 The wine processing plant sold 8/15 of its total wine production to the domestic market, 2/7 to the foreign the rest of the wine. How many percents are still in stock?
  14. Peroxide
    chemia_3 How many ml 30% of peroxide (H2O2) should be poured into 100ml H2O to give a 20% solution?
  15. Pyramid cut
    ihlan_rez We cut the regular square pyramid with a parallel plane to the two parts (see figure). The volume of the smaller pyramid is 20% of the volume of the original one. The bottom of the base of the smaller pyramid has a content of 10 cm2. Find the area of the
  16. Hectoliters
    sudy_4 How many hectoliters of water is in garden barrel with 90 cm diameter and a height of 1.3 m, if it is filled to 80% of its capacity?
  17. Cube into sphere
    cube_sphere_in The cube has brushed a sphere as large as possible. Determine how much percent was the waste.
  18. Inscribed sphere
    cubes2_7 How many percents of the cube volume takes the sphere inscribed into it?
  19. Solutions, mixtures
    roztoky_9 How many liters of 70% solution we must add to 5 liters of 30% solution to give us a 60% solution?
  20. Fruit juice
    cukr_9 Fruit juice contains 37.5% sugar. How many percents of sugar will be in the flavored mineral that we prepare from 100 grams of fruit juice and 1.4 liters of mineral? (1 liter = 1 kg)

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