# Examples for 7th grade (seventh)

1. Hypotenuse Calculate the length of the hypotenuse of a right triangle with a catheti 71 cm and 49 cm long.
2. Parallelogram In the parallelogram we know one internal angle 67°33`. Calculate the other internal angles.
3. Rhombus 4 Circumference of the rhombus is 44 cm, its height is 89 mm long. Calculate its content area.
4. Backpack Large backpack cost CZK 1352, little is 35% cheaper. How much we paid for 5 large and 2 small backpacks?
5. Joshka Joshka had € 15. Mama took him 15%. How many had left?
6. Drainage channel The cross section of the drainage channel is an isosceles trapezoid whose bases have a length of 1.80 m, 0.90 m and arm has length 0.60 meters. Calculate the depth of the channel.
7. Compare: What is bigger? ?
8. Metal box How much metal we need for the production of box with dimensions 5 dm, 30 cm and a height of 1 m? Add 12% of the waste and folds.
9. Johnny Johnny bought for 28 CZK flower to mum. He that spent 4/7 of the money saved. How much money he had saved? How much money left him?
10. Tailor Tailor bought 2 3/4 meters of textile and paid 638 CZK. Determine the price per 1 m of the textile.
11. Cube 6 Surface area of one wall cube is 1600 cm square. How many liters of water can fit into the cube?
12. Ratios Divide: a) 250 CZK in the ratio 2:3 b) 1000 CZK in the ratio 4:7:9
13. Pine wood From a trunk of pine 6m long and 35 cm in diameter with a carved beam with a cross-section in the shape of a square so that the square had the greatest content area. Calculate the length of the sides of a square. Calculate the volume in cubic meters of lu
14. Broken tree The tree was 35 meters high. The tree broke at a height of 10 m above the ground. Top but does not fall off it refuted on the ground. How far from the base of the tree lay its peak?
15. King King had four sons. First inherit 1/2, second 1/4 , third 1/5 of property. What part of the property was left to the last of the brothers?
16. Diameter The diameter of a circular plot is 14 dm. Find the circumference and area.
17. Cuboid 5 Calculate the mass of the cuboid with dimensions of 12 cm; 0.8 dm and 100 mm made from spruce wood (density = 550 kg/m3).
18. Tank How many minutes does it take to fill the tank to 25 cubic meters of water filled 150hl per hour?
19. Ferris wheel Ferris wheel reaches to 22 m tall and moves at the speed of 0.5m/s. During one drive wheel rotates three times. What is the total drive time?
20. 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?

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