Mixtures and solutions - math word problems

  1. Pouring alcohol
    roztoky 100 liters of alcohol has 70% How many liters of water need to be added to have 60% alcohol?
  2. Fruit salad
    banan The fruit salad is prepared from oranges and bananas. One kilogram of oranges costs 30 CZK and one kilogram of bananas costs 18 CZK. How many kilograms of bananas need to be added to half a kilogram of oranges to produce a fruit salad worth CZK 21 per 1 kg
  3. 1st drug
    pirule First drug pack has an active ingredient ratio of L1: L2 = 2: 1 Second drug pack have a ratio of active ingredients L1: L2 = 1: 3 In which ratio do we have to mix the two packages so that the ratio of substances L1: L2 = 1: 2?
  4. Mixture of nuts
    vahy2 The mixture of nuts should be prepared from almonds, peanuts and cashew nuts ratio 1: 2: 3 (respectively). The price of almonds is 150 CZK/kg, the price of peanuts is 140 CZK/kg and the price of cashew nuts is 180 CZK/kg. The price of the mixture is deter
  5. Alcohol
    chemia 6l 48% alcohol, how much 52% alcohol must be added to give 50% alcohol?
  6. Copper sulphate
    CuSO4crystal How much g of water do we have to add to 240 g of an 84% CuSO4 solution to produce a 60% solution? (Express the mass of crystalline CuSO4 in the original solution and in the resulting solution and compare them. )
  7. Two math problems
    coins 1) The sum of twice a number and -6 is nine more than the opposite of that number. Find the number. 2) A collection of 27 coins, all nickels, and dimes, is worth $2.10. How many of each coin are there? The dime, in United States usage, is a ten-cent coi
  8. The painter
    painter_12 In order for the painter to get the desired color, he must mix green and yellow in a ratio of 4: 7. If it has 28 l of green color, how many liters of yellow color should he add? How many liters of mixed color does he get?
  9. Mushrooms
    hriby_1 Mushrooms lose 90% by weight drying. How many fresh mushrooms are needed for 5 kg of dried mushrooms?
  10. Acid evaporation
    roztoky_12 How many kilograms of water do we have to evaporate from 100 kg of 32% acid to make it 80% concentration?
  11. Clogging
    h2o2 How much distilled water must the pharmacist add to 30g of a 30% hydrogen peroxide solution to obtain a 3% solution to clogging?
  12. Vinegar mixing
    vinegar_2 We mix 70g water and 50g 8% vinegar. How many percents of the solution of vinegar we produce?
  13. Mushrooms
    hriby Fresh mushrooms contain 88% water, dried 14% water. How many kilograms of fresh mushrooms should be collected to get 3 kg of dried?
  14. The pool
    inlet_1 The pool contains 220 m3 of water. The pool can be emptied either: a) 10 hours of pipe B and 8 hours of pipe A, or b) 10 hours of pipe A and 7 hours of pipe B. How many cubic meters of water will flow in 1 hour from pipe A and how many from pipe B?
  15. Mixing water
    teplomer_17 The 30-liter container should we fill with water at 60 degrees Celsius. How many liters of water 80 degrees C hot and how many liters of water 20 degrees Celsius warm we have to mix?
  16. Beds
    stan_3 At the summer camp, there are 41 chalets. Some rooms are 3-beds, some 4-beds. How many campers from 140 are living in 3-bed?
  17. Home cleaning
    bleach Mr. Smith is cleaning up a big mess at home. In the closet, he finds a solution that is 5% bleach, and another stronger solution that is 20% bleach. For this particular job, he needs 600mL of 15% bleach. How much of each type (to the nearest mL) should he
  18. Sugars
    vaha2 In what ratio must two sorts of sugar, costing #390 and #315 per kg respectively, be mixed in order to produce a mixture worth #369 per kg?
  19. Fruit tea
    tea_3 Tea contains 7% of fruit components and 12% of sugar in this component. How many percents of sugar is represented in the whole tea?
  20. Peroxide
    chemia_3 How many ml 30% of peroxide (H2O2) should be poured into 100ml H2O to give a 20% solution?

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