# Examples for 7th grade (seventh) - page 77 For the construction of the road dam, it is supposed to transport six trucks a total of 18 days. After three days, two more cars were sent to the construction site. How long will it take to carry the material?
2. Sand The maximum weight of the car is 5000 kg. 10 m3 of sand must be transferred. How many times does a car have to go? (density of sand is 1500 kg/m3)
3. Scale of plan On the plan of the village in the scale of 1: 1000 a rectangular garden is drawn. Its dimensions on the plan are 25mm and 28mm. Determine the area of the garden in ares.
4. Basen How many square meters of tiles we need to tile the walls and floor of the pool 15 meters long, six meters wide and two meters?deep
5. Trees From the total number of trees in the orchard, there are two-fifths pearls and apples are three eighty. The rest of the trees are 9 ceremonial. How many trees are in the set?
6. Triangular prism Calculate a triangular prism if it has a rectangular triangle base with a = 4cm and hypotenuse c = 50mm and height of the prism is 0.12 dm.
7. Container The container-shaped box with internal dimensions of 3.9 m, 3.25 m and 2.6 m was completely filled with goods in the same cubic boxes. How long edge could this box have?
8. Two chords There is a given circle k (center S, radius r). From point A which lies on circle k are starting two chords of length r. What angle does chords make? Draw and measure.
9. Rectangular prism If i have a rectangular prism with a length of 1,000 cm, width of 30 cm and a height of 50 cm, what is the volume?
10. Profit per kilo The trader sells apples at a profit of 20% per kilogram. Today, he decided to reduce the price of apples by 10%. How much profit does the trader have today?
11. Horizontal distance The road has a gradient of 8%. How many meters will the road rise on a horizontal distance of 400m?
12. Irrigation sprinkler The irrigation sprinkler can twist with an angle of 320° and has a reach of 12 meters. Which area can irrigate?
13. Cube The sum of all cube edges is 30cm. Find the surface area of the cube.
14. In the In the national park, the ratio of the wooded area to grassland is 4: 1. The total area is 385km2. What area is wooded?
15. The farmer The farmer had 140 sheep. For the next year, she decided to change the number of sheep in ratio 10: 7. How many sheep will he have then?
16. Line segment The 4 cm long line segment is enlarged in the ratio of 5/2. How many centimeters will measure the new line segment?
17. Digit sum How many are three-digit numbers that have a digit sum of 6?
18. Square Square JKLM has sides of length 24 cm. Point S is the center of LM. Calculate the area of the quadrant JKSM in cm2.
19. Map scale The rectangular plot has in a scale of 1: 10000 area 3 cm2 on the map. What content does this plot have on a 1:5000 scale map?
20. Circular arc Calculate the length of the circular arc if the diameter d = 20cm and the angle alpha = 142 °

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