Ratio - examplesOn 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.
- Sun rays
If the sun's rays are at an angle 60° then famous Great Pyramid of Egypt (which is now high 137.3 meters) has 79.3 m long shadow. Calculate current height of neighboring chefren pyramid whose shadow is measured at the same time 78.8 m and the current hei
- Three workers
Three workers got paid for work. First earn € 50, the second € 100 and third € 60. For further work should receive together € 735. How do you divide that amount in order to be distributed in the same proportion as the first job?
Charlie bought 7 same chocolates for 14 Eur. How many euros he pay for 27 chocolates?
What is better for people (employees)? ?
A cyclist passes 88 km in 4 hours. How many kilometers he pass in 8 hours?
Route is long 203 km and the first day first regiment went at an average speed 20 km/h and journey back 19 km/h. The second day went second regiment same route at an average speed 18 km/h there and back. Which regiment will take route longer?
4 chickens give 4 eggs in 4 days. How many eggs can give 8 chickens for 8 days?
- School trip
School trip cost 340.8 USD for one class (24 students). How much would cost a trip for two classes? (both classes together have 44 students)
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?
Two workers would make installation of greenhouses for 54 hours. For how many hours does the installation 9 workers?
Andrew wrote this series of numbers: 1,3,7,15, .... n. Which number in the series does not belong? ?
- One sixth
How many sixth are two thirds?
The office was attended by 39 people. 9 of them completed the questionnaire. What is the percentage of all people?
Two cats caught two mice in two days. How many mouses will catch 6 cats for 6 days?
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?
6 numbers are in the ratio 3:3:4:4:5:5. Their sum is 264. What are the numbers?
Kevin save € 4620 to buy a car. Yet it lacks save 65% of the car price. How much is the car?
Fields go plow two tractors with various performance. The first tractor plow whole field in 5 hours, the second tractor plow whole field 5 hours longer. How long take plow whole field with two tractors?
- Efficiency of rail
With subsidies are business easy. Calculate how much must cost rail ticket (x) in today's ticket price € 13 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.
- Density - simple example
Material of density of 1278 kg/m3 occupies a container volume of 80 cm3. What is its mass?