Units - examples - page 82

1. Pedestrian
Dana started at 10:00 from the point A to point B. These points are distant 12 km. Determine how fast Daniel went when the place B arrived at 11:54. Speed express in km/h.
2. Sum of money
On a certain sum of money, invested at the rate of 10% compounded annually, the difference between the interests of the first year and the third year is 315 . Find the sum.
3. Excavator
The excavator bucket capacity is 0.5 m3. Determine the mass of sand that the excavator picks up. The sand density is 1650 kg/m3.
4. Cone
Calculate the volume of the rotating cone with a base radius 26.3 cm and a side 38.4 cm long.
What is the diameter of a tree around which is 3m 9dm 7cm long rope wrapped? How big is its cross-sectional area?
6. Sales off
shoes cost x euros. First they are discounted by 50%, and then 25% of the new amount. Determine what percentage of the total cost is cheaper.
7. Square glass
What is the area of the square window glass with the side 4 dm? Do you know how many cm2 is it?
8. Acres
Two hours 24 students harvested chestnuts on 36 acres. How many square meters harvested one student per hour?
9. Can
Watering can full of water weighs 10 kg. Half-full can weighs 5.5 kg. How much weigh can?
10. Cross section
The cross-section ABCD of a swimming pool is a trapezium. Its width AB=14 meters, depth at the shallow end is 1.5 meters and at the deep end is 8 meter. Find the area of the cross-section.
11. Rectangle 35
Find the area of a rectangle when the diagonal is equal to 30 cms and the width is double the length.
12. Apples
Apples I picked 600 kg this year. Autumn's apples was 4 times more than the summer. How many kg's I picked the summer and how much winter apples?
13. Pond
A pond with two open floodgates will emptied in 20 days. A larger floodgate will emptied whole pond in 30 days. For how long would he be emptied with a smaller floodgate.
On a straight stretch of road is marked 12 percent drop. What angle makes the direction of the road with the horizontal plane?
15. Medians of isosceles triangle
The isosceles triangle has a base ABC |AB| = 16 cm and 10 cm long arm. What are the length of medians?
16. Boys and money
270 USD boys divided so that Peter got three times more than Paul and Ivan has 120 USD more than than Paul. How much each received?
17. Regular n-gon
In a regular n-angle polygon the internal angle is 144 degrees. Find the number n indicating the number of sides of this polygon.
18. Two aircraft
From the airport will start simultaneously two planes, which fly tracks are perpendicular to each other. The first flying speed of 680 km/h and the second 840 km/h. Calculate how far the aircraft will fly for half an hour.
19. Socks
One pair of socks worth CZK 27. Set of 3 pairs of these socks are sold with 10% discount. How many we will pay CZK for two offered sets of socks?
20. Way
If the current way to school was 2 km shorter then if Milan swipe one half he will have already one quarter of the way to school behind. How long is Milan's way to school?

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