Ratio - 5th grade (10y) - examples

On solving problems and tasks with proportionally we recommend hint rule of three. Rule of three (proportionality) help solve examples of direct and inverse proportionality. Three members makes possible to calculate the fourth - unknown member.

  1. Chocolate
    cokolada Randy bought 6 same chocolates for 6 Eur. How many euros will he pay for 25 chocolates?
  2. Cyclist
    cyclist_2 A cyclist passes 88 km in 4 hours. How many kilometers he pass in 8 hours?
  3. Chickens
    chickens 2 chickens give 2 eggs in 2 days. How many eggs can give 8 chickens for 8 days?
  4. 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.
  5. School trip
    school_trip School trip cost 90 Eur for one class (20 students). How much would cost a trip for two classes? (both classes together have 40 students)
  6. Cats
    cats Two cats caught two mice in two days. How many mouses will catch 6 cats for 6 days?
  7. 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.
  8. Greenhouses
    sklenik Two workers would make installation of greenhouses for 54 hours. For how many hours does the installation 9 workers?
  9. Floor
    map_mierka The floor area of ​​the room is 31 m2 and has a width of 4.3 m. How many centimeters of circumference measured floor on the map at the scale 1:75?
  10. Efficiency of rail
    vlak With subsidies are business easy. Calculate how much must cost rail ticket (x) in today's ticket price € 11 and if the trains was not subsidized, if it is known that without subsidies would cost three times today's ticket prices. Calculate the value of.
  11. DIY press
    typewriter Under socialism regime was in some socialist countries to own a typewriter requires special permission. That has hindered the spread of DIY literature (manually transcribed through carbon copy paper for typewriters). Calculate how many typewriters today.
  12. The horses
    kon A couple of horses consume 88 kg of oats for 14 days. How many oats consumed 7 horses at the same consumption for 6 days?
  13. Wood
    rubanie_dreva Peter chops wood. If they cut down a half hours a day he ended work in 9 days. But Peter needs to end work 3 days earlier. How many minutes a day should cut down?
  14. Honza + Alice + Tonda
    minca Honza + Alice + Tonda have a total of 111 USD. The ratio between Honza and Alena is 5:6 and the ratio between Alice and Tonda is 4:5 How many money have each of them?
  15. Apples
    apples_1 Mr. Vesely give to the market his own 48 kg of apples, 40 kg from Mr. Kovar and 72 kg of Mr. Novak. Grossed a total of 1,920 CZK. How must divide income money for apples?
  16. Liquid soap
    soap_liquid Three-member family enough liter of liquid soap for 20 days. After how many days the amount consumed when at the holidays come to us two cousins.
  17. Dairy
    mleko_1 Diary workers calculated according to the standards that from the 108 liters of milk is possible to produce 9 kg cheese. How many tons of cheese was possible according to standards make from milk from 100 cows devoted for 30 days with average daily milk.
  18. Rabbits
    zajace_1 Michael breeding rabbits. His 7 rabbits will eat 98 feed rations for 7 days. How many equal portions of feed should be eat 5 rabbits in 6 days?
  19. Cooks
    kucharky Four cooks cleaned 5 kg of potatoes for 10 minutes. How many cook would have to work clean 9 kg of potatoes for 12 minutes?
  20. Ratio of perimeters
    rectangle.JPG Rectangle ABCD has dimensions 3 cm and 4 cm, KLMN rectangle has dimensions 4 cm and 12 cm. Calculate the ratio of the perimeter ABCD and perimeter KLMN.

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