# Units - examples - page 33

1. Skier At this point, the first skier lead 20 km before the second skier and travels at a constant speed 19 km/h. The second skier rides at 24 km/h. How long take him to catch up the first?
2. Cube wall Calculate the cube's diagonal diagonal if you know that the surface of one wall is equal to 36 centimeters square. Please also calculate its volume.
3. Bricks Openings in perforated bricks occupy 10% and brick has dimensions 30 cm, 15 cm and 7.5 cm. Calculate a) the weight of a perforated bricks, if you know that the density of the full brick material is p = 1800 kg/m3 (1.8 kg/dm3) b) the number of perforated.
4. Carbon dioxide Calculate how many grams of oxygen are in 50 g of carbon dioxide CO2. Relative atomic mass of oxygen is 16 and of carbon is 12.
5. School trip 6.A class went on a trip. Train ticket cost 6 euros, cable car ticket 6 euro. How many euros must pay classroom teacher for 23 students?
6. Pumps 3 Two pumps of the same power fill the garden pool for 10 hours. How many of these pumps would have to use if we want to shorten the filling of the pool to four hours?
7. Forest nursery In Forest nursery plant one pine to 1.9 m2. Calculate how many plants are planting in area 362 acres.
8. Clock What distance will pass end of 8 cm long hour hand for 15 minutes?
9. Gon functions Decide which of the numbers (values ​​of trigonometric functions) are positive and which are negative (or zero). Positive mark +1 and negative -1.
10. Pennies 800 pennies have the same value as 100 ducats. 100 pennies have the same value as 250 tolars. How many ducats has the same value as 100 tolars?
11. Pyramid 8 Calculate the volume and the surface area of a regular quadrangular pyramid with the base side 9 cm and side wall with the base has an angle 75°.
12. Retail At what price bought retail 1 kg goods from wholesale, if lost in the distribution is 4% of weight of the goods and retail still have a profit of 6.3%? Goods are sold at retail for 25 euro per kg.
13. Rising price The book first become more expensive by 5 euros. New price was later increased by 8%. After the second price increase book cost 46 euros. What was the original price of the book?
14. Loans, loan ... In Slovakia, launched a short-term non-bank loans, of which few people have their "take" are considered unfavorable. Often, the borrower ends up in a spiral of debt, which takes more and more onerous loan used to repay earlier loans. Calculate how many 9-
15. Water tank 2 Water tank cuboid is 12 meters long and 6.5 meters wide and 1.2 meters high. How many hectoliters are in the tank when it is filled to 81%? What size have angles in quadrilateral (4-gon) if they are in a ratio of 8: 9: 10: 13?
17. Surface area The volume of a cone is 1000 cm3 and the content area of the axis cut is 100 cm2. Calculate the surface area of the cone.
18. Passenger car Passenger car travels 1 km for 2.3 minutes, a truck during a 50 seconds long. How much is the speed of the truck less?
19. A family A family of four pays for garbage collection per year 1800 Kč. How many crowns a year the waste company get from the house where lives 93 people?
20. Milimeters The pool is 6 meters long, 3 meters wide and the water in it is filled with water to a height 1.9 m. When John jumped into it and completely submerged, the level has risen by 4.2 mm. How much weight John when we know that one liter of the human body weighs

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