# Units - examples - page 81

1. Cube walls
Find the volume and surface area of the cube if the area of one wall is 40cm2.
2. Trapezium
The lengths of a parallel sides of a trapezium are (2x+3) and (x+8) and the distance between them is (x+4). if the area of the trapezium is 590 , find the value of x.
3. Oceans
The Earth's surface is approximately 510,000,000 km2 and is 7/10 covered by oceans. Of which 1/2 covers the Pacific Ocean, the Atlantic Ocean 1/4, the Indian Ocean 1/5 and the Arctic Ocean 1/20. What parts of the Earth's surface cover each ocean?
Zahrada má rozměry 5m a 400cm. Kolik pletiva třeba na oplocení pozemku?
How many products weighing 12.5 kg can be loaded on a cargo car with a load of 1.5 t to load two-thirds?
6. Map scale
On a 1:1000 scale map is a rectangular land of 4.2 cm and 5.8 cm. What is the area of this land in square meters?
7. Argicultural field
Field has a rectangular shape with a width 180 m and circumference 940 m. How many hectares acreage has field?
8. Acid solution
By adding 250 grams of a 96% solution of sulfuric acid to its 3% solution its initial concentration was changed to 25%. How many grams of 3% of the acid were used for dilution?
Tadeus and Jolana have a total of CZK 15. Jolana has half that of Tadeus. Nevertheless, Jolana has 3 coins and Tadeus 2. Which coin does Tadeus have and which Jolan?
10. Wine
A bottle of wine costs 21 euros; and wine is 20 times more expensive than a bottle. How much a bottle cost?
11. Triangular prism
The perpendicular triangular prism is a right triangle with a 5 cm leg. The content of the largest wall of the prism is 130 cm2 and the body height is 10 cm. Calculate the body volume.
12. Blackberries
Damián gathered for 19 days 9.5 kg of blackberries. Milada gathered for two days 1.6 kg of currants. How much would collect Damián blackberries per day and how much currants Miladka per day?
13. Rhombus OWES
OWES is a rhombus given that OW 6cm and one diagonal measures 8cm. Find its area?
14. Water temperatures
To 25 liters of water at 50 °C we add 15 liters of water at a different temperature. How many °C should the water be colder than 50 °C so that 40 liters of the water obtained has a temperature 42.5 °C?
15. Syringe and patient
In 1 ampoule of 2 ml is 15 mg of Dipidol. The patient should receive 10 mg. How much ml do I draw into the syringe?
16. Washing mashine
Family buy a washing machine for 350e. Cash paid 280e. What percentage of the total price must still pay the washer?
17. Warehouses
In the three warehouses, a total of 70 tons of grain was stored. In the second warehouse was stored 8.5t less and in the third 3.5t more than in the first. How many tons of grain was stored in each warehouse?
18. Tank diameter
A cylindrical tank has a volume of 60 hectoliters and is 2.5 meters deep. Calculate the tank diameter.
19. Kaufland sales-off
As a rule the goods to the approaching end consumption in Kaufland three days before the end of the consumption to 30% off and one day before the end of the consumption to 50% discounts. Sometimes however the seller has been mistaken and the second discoun
20. Empty canister
The canister is filled with oil weight 17 kg. If filled only half weight 9 kg. What weight does my empty canister have?

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