Mass - 7th grade (12y) - math problems

  1. Iceberg
    ice What is the surface area of 50 cm iceberg (in the shape of a cuboid) that can carry a man with luggage with a total weight of 120 kg?
  2. Tilapia
    tilapia_1 A fish vendor sells 5/7 kilos of tilapia for 73.50. If you will buy 2 1/7 kilos of tilapia, how much will it cost?
  3. A jewelry
    gold A jewelry store has 20 grams of gold. If a pair of earrings need 1/4 gram of gold, how many grams are not used?
  4. Cheops pyramid
    Pyramid-cheops The Pyramid of Cheops is a pyramid with a square base with a side of 233 m and a height of 146.6 m. It made from limestone with a density of 2.7 g/cm3. Calculate the amount of stone in tons. How many trains with 30 twenty tons wagons carry the stone?
  5. Steel tube
    pipe1 The steel tube has an inner diameter of 4 cm and an outer diameter of 4.8 cm. The density of the steel is 7800 kg/m3. Calculate its length if it weighs 15 kg.
  6. Milo lifted
    vaha2_3 Milo lifted 65 lb 6 times and Jeremy lifted 50 lb 9 times. Which one lifted the most weight?
  7. Solid food
    lízátky_1 Stacie is a resident at the medical facility where you work. You are asked to chart the amount of solid food that she consumes. For the noon meal, today she ate 1/2 of a 3-ounce serving of meatloaf, 3/4 of her 3-ounce serving of mashed potatoes, and 1/3 of
  8. 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.
  9. Dried fruit
    hrozienka_1 The manufacturer produces a mixture of dried fruit. He purchased: 10kg pineapple for 200 Kc/kg 2kg papaya for 180 kc/kg 1kg of banana for 400 Kc/kg How many kgs of raisin for 80 Kc/kg must be put into the mix by the manufacturer so that the production pr
  10. Recipe
    vaha2_2 A recipe requires 2 pounds of flour. If a chef wants to triple the recipe, how many ounces of flour will be needed?
  11. Sugar production
    cukrrka_1 From 1 ton of beet, 150 kg of sugar is produced. To clean 1 ton of sugar 450 kg of lime is consumed. Calculate how many kgs of lime is consumed when processing 1 ton of sugar beet?
  12. Floating of wood - Archimedes law
    balza05 What will be the volume of the floating part of a wooden (balsa) block with a density of 200 kg/m3 and a volume of 0.02 m3 that floats in alcohol? (alcohol density is 789 kg/m3)
  13. Gold horseshoe
    podkova Calculate the volume of a gold horseshoe that weighs 750g.
  14. Liter of gold
    zlatovlaska_1 What weight does 1 dm3 of gold have? Gold density is 19,300 kg / m3
  15. Aquarium
    akvarko I have an aquarium that is 100 cm long and 40 cm wide and 40 cm in height. We fill it with water. How much will it weigh?
  16. Car crash
    alkohol-tester-alkohol-za-volantom_2 After a traffic accident, police measured 1.16 permille of alcohol in the driver's blood. What amount of alcohol did the driver have in the blood when about 5 kg of blood circulates in the human body?
  17. 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?
  18. Snowman 3
    snowman_2 During the last winter carnival, the local college students built a 30- foot snowman out of 109 tons of snow. How much snow will be needed to build a 36- foot snowman this year?
  19. Food weight
    vaha_21 Stacie is a resident at the medical facility where you work. You are asked to chart the amount of solid food that she consumes. For the noon meal, today she ate 1/2 of a 3-ounce serving of meatloaf, 3/4 of her 3-ounce serving of mashed potatoes, and 1/3 of
  20. No smoke
    no_smoking Tobacco company NO-SMOKE adorned its stand at the cigarette-type trade fair with the cigarette-shaped. The dimensions of which were 20 times the size of a regular cigarette. The regular cigarette contains 0.8 mg of nicotine. How much nicotine would a giant

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