# Units - examples - page 73

1. Joshka Joshka had € 15. Mama took him 15%. How many had left?
2. Fuel economy How many kilometers is sufficient petrol in the cylinder fuel tank with a diameter 40 cm and the base of tank length 1 m, when it is filled to 60% and if the car consume 15 liters per 100 km?
3. Disc Circumference of the disk is 78.5 cm. What is the circumference of the circular arc of 32° on the disc?
4. Bath salts Bath salt A weighs 900 grams and costs 36,40 CZK. Bath Salts B weighs 1000 grams, but costs 85 CZK. How much is a bath salt A cheaper than B one?
5. Pharmacy The pharmacy add to 3 liters of 95-percent alcohol 5 liters of 38.04 percent alcohol. How many percent pharmacy got?
6. Charles Bridge Charles Bridge was 15 times older than Frantův bridge from 1900 in 1931. How old is the Charles Bridge?
7. Wood lumber Wooden lumber is 4 m long and has a cross section square with side 15 cm. Calculate: a) the volume of lumber b) the weight of the lumber if 1 m3 weighs 790 kg
8. Tank To cuboid tank whose bottom has dimensions of 9 m and 15 m were flow 1080 hectoliters of water. This was filled 40% of the tank volume. Calculate the depth of the tank.
9. Rotatable tower Rotatable tower situated in the city center has ground shape of a regular polygon. If the tower is rotated by 14.4° around its centerpiece it looks from the side same. Your task is to calculate at least how many vertices can have a ground plan view of the.
10. Cylinder surface area Volume of a cylinder whose height is equal to the radius of the base is 678.5 dm3. Calculate its surface area.
11. Blueberries 2 Lenka and Martin collected eight liters of blueberries in two hours. How long will take to collect blueberries by Lenka itself, if we know that she collect all 2.5 hours less than Martin?
12. Straight lines Draw two lines c, d so that c || d. On line c mark points A, B, from point A start perpendicular to line c, from point B perpendicular to line c.
13. Common cylinder I've quite common example of a rotary cylinder. Known: S1 = 1 m2, r = 0.1 m Calculate : v =? V =? You can verify the results?
14. Cycling trip At 8 am started a group of children from the camp to day cycling trip. After 9:00 weather deteriorated sharply and the leader decided to send for the children bus on the same route, which started at 10 hours. For how long and at what distance from the camp
15. Tank How many minutes does it take to fill the tank to 25 cubic meters of water filled 150hl per hour?
16. The shop The shop has 3 hectoliters of water. How many liter bottles is it?
17. Plot The plot on which Mr. Kalous is to build a house has the shape of a rectangle. On a 1: 500 scale, its dimensions are 7cm and 5.5cm. Find out the dimensions of the plot. Calculate the parcel size.
18. Two planes Two planes flying from airports A and B, 420 km distant against each other. Plane from A took off 15 minutes later and flies at an average speed of 40 km/h higher than the plane from B. Determine the average speed of this two aircraft if you know that it
19. Pumps Five pumps pumped 1,800 hl of water for 3 hours. How many hectoliters of water pump same two powerful pumps for six hours?
20. Nightingale Nightingale sang five seconds for 5 hours and 5 minutes. How many seconds were missing to sing 10 hours?

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