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

Number of problems found: 217

  • Sand
    sand_pile How much m ^ 3 of sand can be loaded on a car with a load capacity of 5 t? The sand density is 1600 kg/m3 .
  • Coke and coal
    coal 20.1 tons of coke is produced from 30 tons of black coal. How much coke is made from 1 kilogram of coal?
  • Train tons
    vlak The entire loaded train weighs 760 tons. It has a total of 30 wagons, each carrying 12 tons of grain and empty weighs 10 tons. What is the weight of the locomotive?
  • Ice floe
    ice_cubes What is the volume of an ice floe weighing 326 kg? The density of ice is only 920 kg/m3.
  • The body
    cuboid_3colors The body has dimensions of 2m, 2dm, and 10 cm. It weighs 28 kg. What is its density?
  • Brick wall
    bricks What is the weight of a solid brick wall that is 30 cm wide, 4 m long and 2 m high? The density of the brick is 1500 kg per cubic meter.
  • Olive seeds
    oil_lane 5 kg of oil is pressed from 100 kg of seeds. How many kgs of seeds do we need to produce 85 kg of oil?
  • Save trees
    stromy 25 tons of old paper will save 1,600 trees. How many tons of paper is needed to save the 32 trees in the park?
  • Ratio
    maliny Alena collected 7.8 kg of blueberries, 2.6 kg of blackberries, and 3.9 kg of cranberries. Express the ratio in the smallest natural numbers in this order.
  • The piglet
    piglet The weight of the piglet regularly grew by five kilograms for four months. Determine the proportion by weight of the piglet in each month if the first weighed 35 kg.
  • AL wire
    vaha2 What is the weight of an aluminum wire 250 m long with a diameter of 2 mm, if the density of aluminum is p = 2700 kg/m cubic. Determine to the nearest gram.
  • Brass
    brass Brass is an alloy of copper and zinc in a ratio of 3: 2. How many grams does a component that required 270 g of copper weigh?
  • Bottles
    flasa The weight of 17 bottles is 91.7 kg. What is the weight of 1 bottle?
  • Chestnuts
    vaha Three divisions of nature protectors participated in the collection of chestnut trees.1. the division harvested 1250 kg, the 2nd division by a fifth more than the 1st division and the 3rd division by a sixth more than the second division. How many tons of
  • Oak trunk
    stromy Calculate in tonnes the approximate weight of a cylindrical oak trunk with a diameter of 66 cm and a length of 4 m, knowing that the density of the wood was 800 kg/m³.
  • Cone from cube
    cones From a wooden block, 20 cm high was the turned largest possible cone. Calculate its weight if you know that the density of wood was 850 kg/m3
  • Nutballs
    oriesky The dough for nutballs contains, among other things, two basic raw materials: flour and nuts in a ratio of 2:1. How much flour and how many nuts are needed for 1 kg of dough if "other" is 100g?
  • The bakery
    cake The bakery baked 325 cakes from 25kg flour. How many kg of flour do they need to bake 195 pieces of such cakes?
  • The prison ball
    prisonBall Calculate the density of the material that the prison ball is made from if you know its diameter is 15cm and its weight is approximately 2.3kg. With the help of mathematical-physicochemical tables estimate what material the ball is made from.
  • Weigh in total
    hrozno I put 3/5 kg of grapes into a box which is 1/4kg in weight. How many kilograms do the grapes and the box weigh in total?

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Mass - math problems. Examples for 7th grade (seventh).