Direct relationship - examples

  1. Tree shadow 3
    tree3_1 A 2-meter rod casts a shadow 3.2 m long. How high is a tree with a shadow of 14.4 m ?
  2. Photocopier
    picture A photocopier enlarges a picture in the ratio 7:4. How many times will a picture of size 6cm by 4cm be enlarged to fit on a 30cm by 20 cm page?
  3. Acres
    plocha_1 Two hours 24 students harvested chestnuts on 36 acres. How many square meters harvested one student per hour?
  4. Pills
    pills If it takes 20 minutes to run a batch of 100 pills how many minutes would it take to run a batch of 50 pills
  5. Chocolate
    cokolada Charlie bought 7 same chocolates for 14 Eur. How many euros he pay for 27 chocolates?
  6. Chickens
    chickens 4 chickens give 4 eggs in 4 days. How many eggs can give 8 chickens for 8 days?
  7. Medicament
    tablets Same type of medicament produces a number of manufacturers in a variety of packages with different content of active substance. Pack 1: includes 60 pills of 1200 mg of active substance per pack cost 18 Eur. Pack 2: includes 30 pills of 1000 mg of active s
  8. Blood
    krv In human body the blood is about 7.7% body weight. How many kilograms of blood is in the human body with weight 96 kg?
  9. Greenhouses
    sklenik Two workers would make installation of greenhouses for 54 hours. For how many hours does the installation 9 workers?
  10. Cow
    krava_1 193 cow consumes 13510 kg hay per day. How many kg of hay consume one cow in one day?
  11. Beer
    piva After three 10° beers consumed in a short time there are 7.4 g of alcohol in 5 kg adult human blood. How much is it per mille?
  12. Saving
    cars Kevin save € 4620 to buy a car. Yet it lacks save 65% of the car price. How much is the car?
  13. Ratio
    ratio_1 6 numbers are in the ratio 3:3:4:4:5:5. Their sum is 264. What are the numbers?
  14. Linear independence
    colinear_vectors Determine if vectors u=(3; -3) and v=(0; 3) are linear Linear dependent.
  15. Road repair
    workers_1 Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
  16. Bonus
    moeny Gross wage was 1113 USD including 16% bonus. How many USD were bonuses?
  17. Accidents
    nehoda-pomnik The count of accidents in 1993 caused 8009 women which is 7.1%. How many men caused the accidents?
  18. Excavation
    vykop_ryha Mr. Radoslav calculated that excavation for a water connection dig for 10 days. His friend would take 7 days. Radoslav worked 3 days alone. Then his friend came to help and started on the other end. On what day since the beginning of excavation they met?
  19. Shadow and light
    stin Nine meters height poplar tree has a shadow 16.2 meters long. How long shadow have at the same time Joe if he is 1,4m tall?
  20. Motor oil
    olej 30 liters of oil cost 28.80 Euros. How much cost a liter?

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