Mass - 8th grade (13y) - math problems

Number of problems found: 227

  • Mass
    tubes The thickness of a metallic tube is 1cm and its outer radius is 11cm. Find the mass of such 1m long tube, if the density of the metal is 7.5g per cubic cm.
  • Density - simple example
    mercury Material of density of 1485 kg/m3 occupies a container volume of 65 cm3. What is its mass?
  • Carbon dioxide
    co2 Calculate how many grams of oxygen are in 50 g of carbon dioxide CO2. Relative atomic mass of oxygen is 16 and of carbon is 12.
  • Air mass
    airbaloon What is the weight of the air in a classroom with dimensions 10 m × 10 m × 2.7 m ? The air density is 1.293 kg/m3.
  • Cuboid 5
    drevo_1 Calculate the mass of the cuboid with dimensions of 12 cm; 0.8 dm and 100 mm made from spruce wood (density = 550 kg/m3).
  • Barrel of oil
    dieselbarrel Barrel of oil weighs 283 kg. When it mold 26% oil, weighed 216 kg. What is the mass of the empty barrel?
  • Metal tube
    pipe2 Calculate the metal tube mass 8dm long with the outer radius 5cm and the inner radius 4.5cm and 1cm3 of this metal is 9.5g.
  • Heating plant
    coal_1 Workers dump imported coke at heating plant. On the first day used half of the amount, the second day three quarters the rest and on the third day left 120 tons. How much coke they dump at heating plant?
  • Cacao
    chocholate_2 Cacao contains 34% filling. How many grams of filling are in 130 g cacao.
  • Gold horseshoe
    podkova Calculate the volume of a gold horseshoe that weighs 750g.
  • Bracelet
    ring The silver bracelet weighs 62g and contains 59g of silver. What is the purity of the bracelet?
  • 15.38
    jablone_1 15.38 mg of vitamin C/oz. How much vitamin C is in an orange that weighs 635 oz?
  • Butter fat
    butter A quarter of kg butter contains 82% fat. How many grams of fat are in four cubes of butter?
  • Gold coin
    gold_munzen Gold coin contains 964 promile pure gold, which is 7.16 g. What is the weight of coin in grams?
  • Ice floe
    lad What is the volume of an ice floe weighing 326 kg?
  • Weights
    vahy_1 Marry and John together weighing 49 kg. Their weights are in ratio 1:6. Determine their weights.
  • Mixture
    roztoky_6 How many percentages mixtures do we get by adding 23ml of matter to 89ml of water?
  • Fe vs. H2O
    atoms_Fe The volume of what the body of the same weight is greater - iron or water?
  • Weightlifter
    culturist Weightlifter lifted 75% of its weight. Determine how much weight lifted when he weighs 132 kg.
  • Buoyancy force
    pool An adult male has a volume of about 0.070 m3. How much buoyancy does it affect him when he is completely immersed in water?

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Mass - math word problems. Examples for 8th grade.