Mass - 9th grade (14y) - math problems

Mass is a property of a physical body and a measure of its resistance to acceleration (a change in its state of motion) when a force is applied. An object's mass also determines the strength of its gravitational attraction to other bodies. The basic SI unit of mass is the kilogram (kg). Other are gram, tonne, milligram, etc.

Number of examples found: 167

  • Water percent
    huby A 15 g sample of the substance contains 70% water. After drying, the weight was reduced to 9 g. What percentage of water is now in the sample?
  • Drunk and alcohol
    opilci One drunk measured 2.7 ‰ alcohol in the blood, another 1.75 ‰. How many grams of alcohol in the blood they had if they has 6 kg of blood?
  • Father and son
    family_16 Father and son weigh together 108kg. The father weighs 2.6 times more than his son. How much does weight my father and son count?
  • Bath salts
    salt_1 Bath salt A weighs 900 grams and costs 36,40 CZK. Bath Salts B weighs 1000 grams, but costs 85 CZK. How much is a bath salt A cheaper than B one?
  • Basic form
    time_3 Expressed the ratios of values in the basic form: 0,5 t : 1,2 kg 200 l : 0,15 m3 12 t : 3600 kg 500 kg : 2,5 t 0,9 kg : 500 g 3,6 m : 240 cm 1200 mm : 2,4 m 300 l : 0,3 m3 6 min 30 s : 900 s
  • Potatoes bags
    vrece_zemiakov I have three bags with 21 kg potatoes. The first bag is 5.5 kg more than in the second bag and the third is 0.5 kg more than in the second bag. Determine how many kgs of potatoes is in each bag.
  • Force meter
    archimedes We put the statuette on the force meter. The force meter showed a value 25 N. Then we placed the statuette on the force meter completely immersed in the water. The force meter showed a value 17 N. What is the volume of the statuette?
  • Water wessel
    karafa The vessel containing water has a weight 19 kg. After pouring half the water its weigth 11 kg. What is the weight of the empty vessel?
  • Three friends
    vaha_1 Danica, Lenka and Dalibor have altogether 96 kg. Lenka weighs 75% more than Dalibor and Danica weighs 6 kg more than Dalibor. Determine the weight of Danice, Lenka and Dalibor.
  • Balance
    balance_weight The rod are 1.9 m long hanging weights 4 kg and 1 kg on ends. Where are centre of rod (distance from weight 4 kg) to be in balance?
  • Positional energy
    energy What velocity in km/h must a body weighing 60 kg have for its kinetic energy to be the same as its positional energy at the height 50 m?
  • Freight train
    Freight_train The train carries 525 tons of limestone in 29 wagons. Wagons are 15 tonne and 20 tons. How many is 15 ton and how many is 20 ton wagons?
  • Cargo
    kon-povoz Weight of cargo car is 761 kg. Weight of car is 23% of the total weight of car+cargo. What is the weight of the cargo load?
  • Barrel with water
    sudy_5 The water barrel has a weight of 52 kg. When we pour a quarter of the water, the weight of the barrel is reduced to 40 kg. Determine the weight of the empty barrel.
  • Candies
    bonbons_10 There are two types of candies in the store at 20 CZK/kg and 80 CZK/kg. How much will be cost a mix if we mix 22kg cheaper and 4kg more expensive candies?
  • Meat
    maso Half a kilogram of pork and three-quarters of a kilogram of beef cost total 5.1 USD. One quarter of a kilogram of beef and 1 kilogram of pork cost 4.9 USD. Determine the price of 1 kg of each type of meat.
  • Uranium ore
    uran Uranium ore contains 0.2% of pure uranium and pure uranium contains 0.07% of fissile uranium. How many grams of fissile uranium contains 2800 ton of uranium ore?
  • Confectionery
    cukrovinky The village markets have 5 kinds of sweets, one weighs 31 grams. How many different ways a customer can buy 1.519 kg sweets.
  • Aluminum wire
    drat Aluminum wire of 3 mm diameter has a total weight of 1909 kg and a density of 2700 kg/m3. How long is the wire bundle?
  • Apple variete
    jablka This year, my uncle harvested 350 kg of apples, including 105 kilograms of Ontario, and the rest is Jonathan. Determine what percentage of the Jonathan apples.

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