Multiplication + rational numbers - examples

  1. Compare
    fraction Compare fractions ?. Which fraction of the lower?
  2. Above 100%
    dummy What is 155% of 210?
  3. Logic
    blue-barrel A man drinks a barrel of water for 31 days, woman for 58 days, for how many days they drink barrel together?
  4. 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
  5. Camp
    skauti In the camp are children. 1/4 went on a trip, 1/2 went to bathe and 99 children remained in the room. How many children are in camp?
  6. Time
    time Write time in minutes rounded to one decimal place: 1 h 42 m 22 s.
  7. Discount
    pulover Ladies sweater was twice discounted. First by 17%, then by 17% of the new price. Its final price was 72 USD. Determine the original price of sweater.
  8. Bonus
    moeny Gross wage was 1113 USD including 16% bonus. How many USD were bonuses?
  9. Pool
    swimming-pool The swimming pool is 6 m wide and 14 m long and 185 cm deep. How many hectoliters of water is in it, if the water is 9 cm below its upper edge.
  10. Aircraft
    787 If an airplane flies 730 km/h for 2.2 h, how far does it travel?
  11. Diophantus
    diofantos_1 We know little about this Greek mathematician from Alexandria, except that he lived around 3rd century A.D. Thanks to an admirer of his, who described his life by means of an algebraic riddle, we know at least something about his life. Diophantus's youth l
  12. Parallelogram
    rovnobeznik Calculate the area and perimeter of a parallelogram whose two sides are long a=10 cm b=22 cm and height ha = 4 cm long.
  13. Daily average
    weather_forecast Calculate the average temperature during the day, when 14 hours was 20 °C and 10 hours was 15 °C.
  14. Store
    pave One meter of the textile were discounted by 2.4 USD. Now 6 m of textile cost as before 3 m. Calculate the old and new price of 1 m of the textile.
  15. Server
    p_pro Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
  16. Water
    tanks Mix 61 l of water with temperature of 48 °C, 58 l warm of 57 °C and 47 l water of 39 °C. What is the temperature of the mixed water immediately after mixing?
  17. Math test
    logo_skola In class 6.A are 32 students and the teacher had managed to give tests to 13 students. 13 testes he gave in 6.5 min. How many pupils still haven't test? How long will it take techer to give tests to 34 students?
  18. Motion problem
    dragway From Bratislavy to Martina go car at speed 83 km/h. From Martina to Bratislavy go another car at speed 62 km/h. How many minutes before the meeting will be cars 21 km away?
  19. Bricks
    bricks_truck Brick has volume 2.2 dm3. How many bricks can drive truck with capacity 20 ton? The density of brick is 2 g/cm3.
  20. Wood
    wood_cube Wood cube with edge 10.5 cm weights 0.434 kg. What weight have 10, 100 and 1000 these cubes?

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