# Examples for 7th grade (seventh)

1. The cube
The cube has an edge of 25 cm. We cut it into small cubes of 5 cm long side. How many of these little ones left when we build a new cube of 20 cm in length?
2. Mixing Celsius and Fahrenheit
Add up three temperatures: 5°F +6°F +0°C
3. Cube root
For 13, Sam wrote 2891 instead of the correct cube number. By how much was he wrong?
4. Flowerbed
Ondra digs the bed in 20 minutes. Cuba in 30 minutes. For how long do they dig together?
5. Inlet minus outlet
Water flows into the tank through two pipes and flows out of the third pipe spontaneously. The pipe A itself would fill the tank in 3 hours, the pipe B itself would fille in 4 hours, and the pipe C itself would flow out in 12 hours. How long will the tank
6. Pencil cut
Veronika cut 10cm pencil. Each turn, the pencil was reduced by 0.2mm. She turned the pencil 100 times. How many centimeters has a pencil now?
7. Tony works
Tony works as a welder for a construction company. His hourly wage is \$15.51 and he works 40 hours per week. Tony gets a paid vacation each year. The construction company is doing well and has plenty of work for the next year. Tony can expect to work the
8. 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?
9. Poplar
How tall is a poplar by the river, if we know that 1/5 of its total height is a trunk, 1/10th of the height is the root and 35m from the trunk to the top of the poplar?
10. Wood dividing
Which equation calculates the number of 1/3-foot pieces that can be cut from a piece of wood that is 7 feet long?
11. Velocipedes
In the 19th century, bicycles did not have a chain drive, and the pedals were connected directly to the wheel axis. This wheel diameter gradually increased until the so-called high bicycles (velocipedes) with a front wheel diameter of up to 1.5 meters, wh
12. Closed drum
Find the total surface area of a closed cylindrical drum if it's diameter is 50 cm and height is 45 cm . (π= 3.14)
13. Constant motion
The car has undergone constant motion 120 km in 1 hour 30 minutes. Determine its average speed. Determine how long car drove in the first 20 minutes and 50 minutes from the start of the move.
14. Greg and Bill
Greg is 18 years old. He is 6 less than 4 times Bill's age. How old is Bill?
15. Pumps
After the floods, four equally powerful pumps exhausted water from the flooded cellar in 6 hours. How many hours would take a drained out with three equally powerful pumps?
16. Round-trip
A woman works at a law firm in city A which is about 50 miles from city B. She must go to the law library in city B to get a document. Find how long it takes her to drive​ round-trip if she averages 40 mph.
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?
18. Sum of dividend
If X is divided separately 2.63 and 1.40. And the results of the individual divisions are added to give a result less than X. What is X?
19. Half-sphere roof
The roof above the castle tower has the shape of a 12.8 m diameter half-sphere. What is the cost of this roof, if the cost of 1 square meter is 12 euros and 40 cents?
20. The number
The number of 1 cm cubes required to make 4 cm cube is?

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