Reason + direct relationship - examples

1. Pool
If water flows into the pool by two inlets, fill the whole for 18 hours. First inlet filled pool 6 hour longer than second. How long pool is filled with two inlets separately?
2. 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 is needed to complete planting trees in nurseries by others, if they will work 10 hours a da
3. Bonus
Gross wage was 527 EUR including 16% bonus. How many EUR were bonuses?
4. Excavation
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. Chickens
2 chickens give 2 eggs in 2 days. How many eggs can give 8 chickens for 8 days?
6. Blood
In human body the blood is about 7.2% body weight. How many kilograms of blood is in the human body with weight 93 kg?
7. Washer
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?
8. Youth track
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.
9. Cyclist
Cyclist goes uphill 10 km for 50 minutes and downhill minutes for 29 minutes, both applied to the pedals same force. How long he pass 10 km by plane?
10. Gear
Two gears, fit into each other, has transfer 2:3. Centres of gears are spaced 82 cm. What are the radii of the gears?
11. TV fail
The TV has after 10,000 hours average 25 failures. Determine the probability of TV failure after 200 hours of operation.
12. Accidents
The count of accidents in 1995 caused 8780 women which is 8.4%. How many men caused the accidents?
13. Division
Three siblings Helena, Oliver and George split the bag with candies on merit in the ratio 6:1:4. How many candies should each get if in bag were 88?
14. Election mathematics
In elections, 12 political parties received this shares of voters: party A 56.2 %party B 8.5 %party C 8.2 %party D 6.2 %party E 6.1 %party F 5.5 %party G 3.2 %party H 2.1 %party I 2 %party J 1 %party K 1 % Calculate what the shares acquired in the parlia
15. Sea on the Moon
Assume that the Moon has sea, the same composition as on the Earth (has same density of salt water). Calculate dive of boat floating in the sea on the Moon, when on Earth has dive 3.6 m. Consider that the Moon has 6.5-times smaller gravitational accelerati
16. Leveling
Calculate how many 25 kg bags of leveling concrete must be purchased if we leveling room 15 m2 to the "height" 6 mm if consumtion is 1.5 kg per square meter and millimeter thickness.
17. Sales vs profit
Apple sells 22 percent less computes than the Acer but the profit from their sales is 2.2 times higher than Acer. How many times are Apple computer more expensive than Acer?
18. Baker
The baker makes from 10 kg of flour 12 kg dough. How much flour he need to make a 100 kg dough?
19. Salary
Calculate equivalent annual salary to hourly salary \$ 19. Assume a 42-hour work week.
20. Divers
20-member group of divers carries the air for 15 hours of diving. 4 members of the expedition sick or wasn't came. How many hours is sufficient air to other divers?

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