# Units - examples - page 42

1. Shaving
Mathematical problem from Sunday evening. If the beard is growing at 0.52 mm per day and that my length is 16.8 mm, how long I don't shave?
2. Garden pool
Mr. Novak fill garden pool (cylinder; diameter of 200 cm) with 31.4 hl of water. What is the depth of the pool when the water level is 10 cm below the upper edge of the pool?
3. Cube basics
How long is the edge length of a cube with volume 23 m3?
4. Tailor
Tailor has an estimated 11 meters of 80 cm wide fabric. He will shape wholly 7 rectangles measuring 80 x 150 cm and nothing fabric does not remain. How many fabric he have?
5. The wall
We have to build a cuboid wall with dimensions base 30 cm and 45 cm and height 3.25 meters. Calculate how many we need bricks if we spend 400 pieces of bricks to 1 m3 of wall?
6. Water level
How high reaches the water in the cylindrical barell with a diameter of 12 cm if there is a liter of water? Express in cm with an accuracy of 1 decimal place.
7. Water pool
Pool with volume 990hl completely filled, if water flows by one tap 8 hours and by second tap 6 hours. First tap give 10hl more than second per hour. How many hl flows in each of them in an hour?
8. Blackjack TU160
Bomber Tupolev TU160 started at 9:00 from the airport and flew at average speed of 1850 km/h toward the airfield B distant 3500 km. After evaluating the danger from the airport B started at 9:45 B towards A fighter MIG 29 at an average speed 2300 km/h. At
9. Diameter
What is the inside diameter of the cylinder container and if half a liter of water reaches a height 15 cm?
10. Tetrahedral prism - rhomboid base
Calculate the area and volume tetrahedral prism that has base rhomboid shape and its dimensions are: a = 12 cm, b = 70 mm, v_a = 6 cm, v_h = 1 dm.
11. Canister
Gasoline is stored in a cuboid canister having dimensions 44.5 cm, 30 cm, 16 cm. What is the total weight of a full canister when one cubic meter of gasoline weighs 710 kg and the weight of empty canister is 1.5 kg?
12. Slope RR
A line has a rise of 2 and a run of 11. What is the slope?
13. Cuboid - simple
Calculate the surface area and volume of a cuboid if a = 8 cm, b = 14 cm and c = 6 cm.
14. Mixing
If we mix 5 kg of goods of one kind and 3 kg second one, resulting mixture cost 16.50 EUR/kg. If these quantities are mixed in reverse - first three kilograms and 5 kilograms second cost of mixture is 18.50 EUR/kg. What is the price of one kg of goods of.
15. Tree
How tall is the tree that observed in the visual angle of 52°? If I stand 5 m from the tree and eyes are two meters above the ground.
Car started at 11:40 at speed 54 km/h from A and to B arrived at 12:20. Determine the distance A and B.
17. Semicircle
To a semicircle with diameter 10 cm inscribe square. What is the length of square sides?
18. Rhombus
ABCD is a rhombus, ABD is an equilateral triangle and AC is equal to 4. Find the area of the rhombus.
19. Two wine
In 2:1 mix wine solution cost 4.1 USD. In 1:2 mix wine solution cost 4.5 USD. How much cost liter of each wine?
20. Traffic collision
When investigating a traffic accident, it was found that the driver stopped the vehicle immediately after the accident by constant braking on a 150 m track in 15 seconds. Do you approve that the driver exceeded the permitted speed (50 km/h) in the village.

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