# Examples for 7th grade (seventh) - page 43

1. Oak cuboid
Oak timber is rectangular shaped with dimensions of 2m, 30 cm and 15 cm. It weight is 70 kg. Calculate the weight 1 dm³ of timber.
2. Equation
Solve equation and check the result: 1.4x - 3/2 + x - 9,8 = x + 0,4/3 - 7 + 1,6/6
3. Diagonals
Draw a square ABCD whose diagonals have a length of 6 cm
4. Sisters
Sisters Janka and Danka are saved together 220 CZK. On a trip to Janka wants to take a fifth of her savings and Danka quarter. Then they will have 50 CZK on the trip. How much money saved Janka and Danka?
5. Triangular prism
Calculate the volume and surface of the triangular prism ABCDEF with base of a isosceles triangle. Base's height is 16 cm, leg 10 cm, base height vc = 6 cm. The prism height is 9 cm.
6. Resort
In a completely crowded resort was 30% from the Czech Republic quarter visitors were from Slovakia and the rest 135 came from Germany. What capacity have resort?
7. Plan scale
At what scale is drawn plan of the building, where one side of the building is 45 meters long is on the plan expressed by a straight line 12 mm long.
I longer watch processors for Socket A on ebay, Athlon XP 1.86GHz with a PR rating of 2500+ costs \$7 and Athlon XP 2.16Ghz with a PR rating of 3000+ currently cost \$16. Calculate: About what percentage of the Athlon XP 2.16Ghz is powerful than Athlon X
9. Cable
Cable consists of 8 strands, each strand consists of 12 wires with diameter d = 0.5 mm. Calculate the cross-section of the cable.
10. Giant coin
From coinage metal was produced giant coin and was applied so much metal, such as production of 10 million actual coins. What has this giant coin diameter and thickness, if the ratio of diameter to thickness is the same as a real coin, which has a diameter
11. Ski class
Class attend 30 boys and some number of girls. Ski training was attended by 28 boys and all the girls, which was 95% of all students. How many girls attend this class? How many percent is that?
12. Two friends
Two friends met as a good man perish together for a beer. After recovery the most important topics (politics, women, football ...), one asks: - And how many do you have children? - I have 3 children. - And how many years have? Friend already not want to an
13. Two looms
On two different looms with different performance can be make required quantity of textile in 6 hours when both work together. On the first machine this quantity of the textile can make in 10 hours. How long should take make same quantity of textile on a s
14. The game of blind man's buff
Slovak levy system makes the gross wage deductions from your pay state employees. It has two components - part employee pays and part pays by the employer Suppose that the super gross wage paid 23% employer. After deducting these contributions we receive g
15. Birds
On the farm they have a total of 110 birds. Geese and turkeys together is 47. Hens is three times more than the turkey. How much is poultry by species?
16. Gearing
Gearing consists of two wheels, one is 88 and second 56 teeth. How many times turns smaller wheel to fit the same teeth as in the beginning? How many times will turn biggest wheel?
17. Highway
Six trucks will be used to build the roadside 18 days. After 3 days, two more trucks were sent to build. How long will it take for material move?
18. Tmp workers
Three temporary workers cleaned 60 m of walkway in 5 hours. How many meters of the walkway cleared seven volunteers for eight hours?
19. Minute
Two boys started from one place. First went north at velocity 3 m/s and the second to the east with velocity 4 m/s. How far apart they are after minute?
20. Grass garden
Mr. Grass would itself be mowed garden for 5 hours. His son Michael could do it for 7 hours. They agreed that they wake up at 5 am and begins to mow together. Ms. Grass needs drive into town at 8.30. Michael says that at that time they're done with work..

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