Mass - 8th grade (13y) - examples

Do you want to convert mass units?

  1. Iron collecting
    paper_1 Class 7A collected 3.2 tonnes of iron more than class 7B. Together they collected 6.4 tonnes of iron to the secondary raw material collection. How much did each class collect?
  2. Calf
    tela The weight of the calf meat obtained is 65% of the total weight of live calves. What was the weight of a calf from which 285 kg of meat was obtained?
  3. Beer
    piva After three 10° beers consumed in a short time there are 5.2 g of alcohol in 6 kg adult human blood. How much is it per mille?
  4. Coffee
    coffe In stock are three kinds of branded coffee prices: I. kind......5.3 USD/kg II. kind......11.6 USD/kg III. kind.....5.8 USD/kg Mixing these three species in the ratio 2:8:3 create a mixture. What will be the price of 800 grams of this mixture?
  5. Sphere
    1sphere Surface of the sphere is 2260 cm2, weight is 52.2 kg. What is its density?
  6. Eiffel Tower
    eiffel_tower Eiffel Tower in Paris is 300 meters high, is made of steel. Its weight is 8000 tons. How tall is the tower model made ​​of the same material, if it weigh is 4.8 kg?
  7. Vinegar 2
    ocet How many percentage of getvinegar solution, if we mix to 14.5 liters of 7.8% and 2.5 liters of 5.8% vinegar?
  8. Density - simple example
    mercury Material of density of 1278 kg/m3 occupies a container volume of 80 cm3. What is its mass?
  9. Alcohol
    no_alcohol How many 46% alcohol we need to pour into 3 liters 63% alcohol to get p3% of the alcohol? How many 52% alcohol we get?
  10. Tare
    camion Gross weight of shipment is 5073 kg and its tare is 6.9%. Calculate the net weight of the shipment.
  11. Barrel of oil
    dieselbarrel Barrel of oil weighs 238 kg. When it mold 20% oil, weighed 196 kg. What is the mass of the empty barrel?
  12. Cu thief
    trolleywire_1 The thief stole 121 meters copper wire with cross-section area of 101 mm2. Calculate how much money gets in the scrap redemption, if redeemed copper for 5.5 eur/kg? The density of copper is 8.96 t/m3.
  13. Air mass
    airbaloon What is the weight of the air in a classroom with dimensions 5 m × 2 m × 3.1 m ? The air density is 1.293 kg/m3.
  14. Pump
    pumpa What power has a pump output to move 4502 hl of water to a height of 32 m for 5 hours?
  15. Plastic pipe
    pvc-trubka Calculate weight of the plastic pipe with diameter d = 60 mm and length 400 cm if the wall thickness is 6 mm and the density of plastic is 1228 kg/m3.
  16. Pizza
    pizza_2 Pizza with a diameter 41 cm have weight 531 g. What diameter will have a pizza weighing 749 g if it is make from the same cloth (same thickness....) and same decorated?
  17. Hollow sphere
    Xmas_ball Calculate the weight of a hollow brass sphere (density 8.5 g/cm3), if the outer diameter is 10 cm and wall thickness is 3 mm.
  18. Cube
    kocka_rubik The cube weighs 47 kg. How weight is cube of the same material, if its dimensions are 3-times smaller?
  19. Metallurgical enterprise
    iron_industry Metallurgical company daily produces 873 tons of cast iron. How many tons of coke it burns to melt cast iron when 17 tons of cast consumes 13 tons of coke?
  20. Canopy
    cone-roof Mr Peter has metal roof cone shape with a height of 36 cm and radius 73 cm over well. He needs paint the roof with anticorrosion. How many kg of color must he buy if the manufacturer specifies the consumption of 1 kg to 2.1 m2?

Do you have interesting mathematical example that you can't solve it? Enter it and we can try to solve it.



To this e-mail address we will reply solution; solved examples are also published here. Please enter e-mail correctly and check whether you don't have a full mailbox.