# Equation + unit conversion - examples

1. Motion problem
From Levíc to Košíc go car at speed 81 km/h. From Košíc to Levíc go another car at speed 69 km/h. How many minutes before the meeting will be cars 27 km away?
2. Beer
After three 10° beers consumed in a short time there are 5.6 g of alcohol in 6 kg adult human blood. How much is it per mille?
3. Motion
If you go at speed 3.7 km/h, you come to the station 42 minutes after leaving train. If you go by bike to the station at speed 27 km/h, you come to the station 56 minutes before its departure. How far is the train station?
4. Clock
How many times a day hands on a clock overlap?
5. Server
Calculate how many average minutes a year is the web server is unavailable, the availability is 99.99%.
6. Motion2
Cyclist started out of town at 19 km/h. After 0.7 hours car started behind him in the same direction and caught up with him for 23 minutes. How fast and how long went car from the city to caught cyclist?
7. Reconstruction of the corridor
Calculate how many minutes will be reduced to travel 187 km long railway corridor, where the maximum speed increases from 120 km/h to 160 km/h. Calculate how many minutes will shorten travel time, if we consider that the train must stop at 6 stations, eac
8. Ships
At 8:40 the ship set sail at 12 km/h. At 19:10 followed by at 29 km/h sail boat. When sail boat catches up the ship? How many minutes will catch up took?
9. Water inlets
Inlet valve with a flow rate of 12 liters per second is filled tank for 72 minutes. How long take to fill full tank if we open one more such valve half an hour after?
10. Pedestrian and cyclist
Pedestrian out with a speed of 4 km/hour from city center and after 1hour and 10 minutes came after him cyclist at speed of 18 km/h. At how many minutes he catches up with pedestrian?
11. Thrift woman
Calculate how long grandmother will save to new shoes priced 108 euros if save 3 Eur monthly.
12. Wood
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?
13. Aircraft
The aircraft has in a fuel tank 68 hl of aviation fuel and flight consumes 3.6 liters of fuel. Identify the function, which expresses the dependence of the volume of fuel in tank on the track distance plane flew by. How many hectolites of fuel is still in
14. Bronze, tin and copper
Bronze is an alloy of tin and copper. An alloy of 10% tin and 90% copper is Gunmetal. If it contains 20% tin and 80% copper, it is bell metal. How many tons of molten bell metal and how many tons of copper is needed to make 100 tons of Gunmetal?
15. Tourist
Tourist walk at 4.1 km/h. Every 5 km have 20-minute break. How many kilometers passed, when started at 4:40 and finished at 10:30?
16. Electrics - conductor
The wire is 106 meters long at 0 °C and at every temperature increase of 1 °C the length increases by 0.15 mm per 1 m length of wire. Determine a function which represents the overall length of the wire as a function of temperature. What is the length of t
Tree perpendicular to the horizontal surface has a shadow 8.32 meters long. At the same time meter rod perpendicular to the horizontal surface has shadow 64 cm long. How tall is tree?
18. Salary
Mr. Johnson's had monthly salary 955 USD since the beginning of year. From which month his salary was increased by 52 USD, when in year earned 11824 USD (enter as a number from 1 to 12)?
19. Wood
Wood contains 12% water. 1 m3 of wood weighs 650 kg. How many liters of water it contains?
20. Pumps
First pump flows 16 liters per second into the basin by the second pump 75% of the first and by third pump half more than the second. How long will take fill basin by all three pumps simultaneously volume 15 m3 (cubic meters)?

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