# Examples for 7th grade (seventh) - page 74

1. Steps Walkway from the house to the school is 180 m long. How many more steps Michael makes than his father on the way to school, if the length of Michael's step is 60 cm and the length of his father's step is 90 cm.
2. Annual rainfall The average annual rainfall is 686 mm. How many liters will fall on the 1-hectare field?
3. Cube surface and volume Find the surface of the cube with a volume of 27 dm3.
4. Brackets 2 Add parenthesis to make true: 5-2×6-4+2=5
5. How much How much money will we pay for 20 planks 4m long, 15cm wide and 26mm thick when 1m³ of wood costs 4500kč?
6. Tourist A tourist walked an average speed of 3.5 km/h route in 6 hours. Calculate how many hours he would have passed at an average speed of 5.5 km/h.
7. Savings Eva borrowed 1/3 of her savings to her brother, 1/2 of savings spent in the store and 7 euros left. How much did she save?
8. 7 digit number If 3c54d10 is divisible by 330, what is the sum of c and d?
9. Flowerbed Ondra digs the bed in 20 minutes. Cuba in 30 minutes. For how long do they dig together?
10. Resistance of the resistor The resistor terminals have a voltage of 20 V and a current of 5 mA is passed through. What is the resistance of the resistor?
11. Ratio of sides 2 The ratio of the side lengths of one square to another is 1:2. Find the ratio of the area of the two squares.
12. Soldier An experienced soldier digs a good trench in 30 hours. Two soldiers dug the same trench each 40 hours. How many hours will the ditch dig all three together?
13. Budget plan In the construction of the building, the planned budget exceeded 13%, which was 32,500 euros. How many euros cost built the building?
14. Is right triangle or not If right triangle ABC, have sides a=13, b=11.5, c=22.5. Find area.
15. Workers Two workers will construct the stage at the festival in 54 hours. Organizers need to shorten the assembly time by 42 hours. How many workers must the assembly company send?
16. Tractors 5 tractors will plow the field for 8 hours. In 2 hours, 1 tractor broke down. How long do the remaining tractors complete the plow?
17. Passenger boat Two-fifths of the passengers in the passenger boat were boys. 1/3 of them were girls and the rest were adult. If there were 60 passengers in the boat, how many more boys than adult were there?
18. Seven Seven friends agree to send everyone a holiday card. How many postcards were sent?
19. Children's pool Children's pool at the swimming pool is 10m long, 5m wide and 50cm deep. Calculate: (a) how many m2 of tiles are needed for lining the perimeter walls of the pool? (b) how many hectoliters of water will fit into the pool?
20. Dd 2-digit numbers Find all odd 2-digit natural numbers compiled from digits 1; 3; 4; 6; 8 if the digits are not repeated.

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