7th grade (12y) + direct relationship - examples

  1. A sculptor
    statue A sculptor is duplicating a statue based on an original statue. If the scale factor of the replication is 3.2, will the new statue be larger or smaller than the original statue (enter 1 = larger, 0= smaller)
  2. Forestry workers
    forestry_workers In the forest is employed 56 laborers planting trees in nurseries. For 8 hour work day would end job in 37 days. After 16 days, 9 laborers go forth? How many days are needed to complete planting trees in nurseries by others, if they will work 10 hours a d
  3. Bonus
    moeny Gross wage was 527 EUR including 16% bonus. How many EUR were bonuses?
  4. Excavation
    vykop_ryha Mr. Billy calculated that excavation for a water connection dig for 12 days. His friend would take 10 days. Billy 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?
  5. Coffee
    coffe In stock are three kinds of branded coffee prices: I. kind......248 Kč/kg II. kind......134 Kč/kg III. kind.....270 Kč/kg Mixing these three species in the ratio 10:7:7 create a mixture. What will be the price of 1100 grams of this mixture?
  6. 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 600 mg of active substance per pack cost 9 Eur. Pack 2: includes 150 pills of 500 mg of active sub
  7. Rectangular cuboid
    cuboid_1 The rectangular cuboid has a surface area 5334 cm2, its dimensions are in the ratio 2:4:5. Find the volume of this rectangular cuboid.
  8. Washer
    pracka Washing machine drum wash at 55 RPM. Washing machine motor pulley has diameter 6 cm. What must be the diameter of the drum machine pulley when the motor is at 333 RPM?
  9. ŽSR
    luzianky Calculate fixed annual personnel costs of operating monorail line 118 km long if every 5 km is station, which serve three people - one dispatcher and two switchman in 4-shift operation. Consider the average salary of the employee 885 €.
  10. Youth track
    tunel Youth track from Hronská Dúbrava to Banská Štiavnica which announced cancellation attracted considerable media attention and public opposition, has cost 6.3 euro per capita and revenue 13 cents per capita. Calculate size of subsidies to trip group of 28.
  11. Two squares
    squares2 Two squares whose sides are in the ratio 5:2 have sum of its perimeters 73 cm. Calculate the sum of area this two squares.
  12. Pediatrician
    doctor Pediatrician this month of 19 working days takes 3 days holidays. What is the probability that on Monday will be at work?
  13. Gear
    ozubene_kolesa Two gears, fit into each other, has transfer 2:3. Centres of gears are spaced 82 cm. What are the radii of the gears?
  14. Greenhouses
    sklenik Two workers would make installation of greenhouses for 54 hours. For how many hours does the installation 9 workers?
  15. Expansion
    magnification If one side of the rectangle is larger 4-times and second 2-times, what percentage increases the area of rectangle?
  16. Arc
    arc_1 Circle arc corresponding to angle is 32° is 28 dm long. What is the length of the entire circle?
  17. Car range
    Lupo_3L_TDI.JPG Calculate the maximum range of car, if you can spend 10 euros, price of diesel is 1.55 Eur/l and car consumption is 3 l/100 km.
  18. Negative percentage
    trabant In 2004, the company had a loss of 40900 Euros. Two years later he was already in profit 48900 Eur. Calculate what percentage of the company increased profits in this two years.
  19. Saving
    cars Allen save € 2860 to buy a car. Yet it lacks save 55% of the car price. How much is the car?
  20. Pizza
    pizza_2 Pizza with a diameter 50 cm have weight 559 g. What diameter will have a pizza weighing 855 g if it is make from the same cloth (same thickness....) and same decorated?

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