# Examples for 7th grade (seventh) - page 20

- Strawberries

Father collects strawberries himself in 4 hours, son in 14 hours. How long will it take them along when dad comes to help son collect strawberries after 3 hours? - Copper plate

Copper plate length 3.2 m and width 50 cm weighs 55.42 kg. What is the plate thick, if 1 m^{3}of copper weighs about 8700 kg? - Unions

Calculate how much money per year would go to the treasury of unions if 218 thousand employee join unions with an average net salary of 407 euros and if memberhip in union cost 1% of the net monthly salary. - 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? - Flowerbed 2

Around the square flower bed in a park is sidewalk 2 m wide. The area of this sidewalk is 243 m^{2}. What is the area of the flowerbed? - Cube and water

How many liters of water can fit into a cube with an edge length of 0.11 m? - 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? - RT and ratio

Right triangle whose cathetus are in a ratio 7:14 has hypotenuse 78 m long. How long are cathetus? - 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? - Four-digit number

Find also a four-digit number, which quadrupled written backwards is the same number. - Water

On the lawn which has area 914 m^{2}rained 3 mm of water. How many liters of water rained? - 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. - Map 2

At what scale is made map if the distance 8.2 km corresponds on the map segment 5 cm long? - Number

Is number 5.146852 irrational? - 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? - Building base

Excavation for the building base is 350x600x26000. Calculate its volume in m^{3}. - Beer

Which beer is better to drink: small beer (0.3 L) for 0.67 € or large (0.5 L) for 1.81 €? - The body

The body on the figure consists of cubes with an edge length 10 cm. What surface has this body? - Addends

Number 839 divide into the two addends that the first was 17 greater than 60% of the second. Determine these addends. - 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?

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