Examples for 7th grade (seventh) - page 19

1. Painter 3 Dad want to paint wall high 250 cm wide and 230 cm with wallpaper. How many meters must buy wallpaper if wallpaper width is 60 cm?
2. Cuboids in cube How many cuboids with dimensions of 6 cm, 8 cm and 12 cm can fit into a cube with side 96 centimeters?
3. Cube and water How many liters of water can fit into a cube with an edge length of 0.11 m?
4. Flowerbed 2 Around the square flower bed in a park is sidewalk 2 m wide. The area of ​​this sidewalk is 243 m2. What is the area of the flowerbed?
5. Four-digit number Find also a four-digit number, which quadrupled written backwards is the same number.
6. RT and ratio A right triangle whose legs are in a ratio 6:12 has hypotenuse 68 m long. How long are its legs?
7. Swing A child weighing 12 kg is sitting on a swing at a distance of 130 cm from the axis of rotation. How far away from the axis of rotation (center) must sit down his mother weighs 57 kg if she wants to be swing in balance?
8. Trapezoid ABCD Calculate the perimeter of trapezoid ABCD if we know the side c=15, b=19 which is also a height and side d=20.
9. The body The body on the figure consists of cubes with an edge length 10 cm. What surface has this body?
10. Map 2 At what scale is made map if the distance 8.2 km corresponds on the map segment 5 cm long?
11. Water On the lawn which has area 914 m2 rained 3 mm of water. How many liters of water rained?
12. Number Is number 5.146852 irrational?
13. Building base Excavation for the building base is 350x600x26000. Calculate its volume in m3.
14. Revenue Mr. Robert and Mr. Norbert get together € 1400. The revenue split in the ratio of 4:3, depending upon each work. How many got each of them?
15. Beer Which beer is better to drink: small beer (0.3 L) for 0.67 € or large (0.5 L) for 1.81 €? Number 839 divide into the two addends that the first was 17 greater than 60% of the second. Determine these addends.
17. Soil pit Workers dug a pit cube with edge 2.5 meters. How many cars shall remove soil if the car suddenly take 4m³ of soil?
18. Cubes Carol with cut bar 12 cm x 12 cm x 135 cm to the cubes. Find the sum of all the surfaces of the resulting cubes.
19. Mother and daughter Three years ago mother was three times older than daughter. After nine years she will be only twice old. How old is mother (and daughter)?
20. VAT VAT is a tax which the state artificially betrays goods and services for final consumption. VAT in Slovakia is 20%. Calculate how much percent pay less tax residents of Liechtenstein, when VAT is only 8%.

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