# Examples for 7th grade (seventh) - page 63

1. Gasoline
How many liters of gas is in the tank if its weight 15.4kg. Specific density of gasoline is 770kg/m3.
2. Central park in city
The city park has the shape of a rectangle of 180 meters in length and 120 meters in width. People make their walk through the center of the park from one corner to the second. Calculate how many meters this way is shorter than they walked along the path.
3. Square
Calculate the perimeter and the area of square with a diagonal length 30 cm.
4. Summerjobs
The agency give summerjobs for 2352 students in 2018. The eighth was high-school students, the rest was undergraduates. How many undergraduates works via agency in 2018?
5. Contract
8 employees complete the contract for 65 hours. After 17 hours, 3 employees had to leave for another job. How many more hours will the job on contract be fulfilled?
6. Workers
9 workers dig a canal 120 meters long for eight hours. For how long would be dig five workers canal 200 meters long?
7. Three workers
Three workers got paid for work. First earn € 50, the second € 100 and third € 60. For further work should receive together € 735. How do you divide that amount in order to be distributed in the same proportion as the first job?
8. Candies
The price for 1 kg of more expensive candies is 125 CZK. The price for 1 kg of cheaper candy is 100 CZK. We mix two different mixtures of candy. A) The first mixture contains 2 kg more expensive and 0.5 kg cheaper candy. Calculate the price for 1 kg of t
9. Liquid soap
Liquid soap lasted two weeks to one member of the family. How many days will last, if it use: a) two members b) 4 members c) seven members?
10. Tailor master
There are less than 50m of textile in the tailoring workshop. When cutting on a blouse (consumption 1.5m), no textile is left. When using a cloth (consumption of 3.2m), no textile is left. How many meters of textile are in a tailor's workshop?
11. Cyclist and car
A cyclist who runs at a speed of 20km per hour will arrive at the finish in 4.5 hours. How fast does the car have to drive the same route in 2 hours?
12. Liter of gold
What weight does 1 dm3 of gold have? Gold density is 19,300 kg / m3
13. Two monuments
The distance between two historical monuments on a map with a scale of 1: 500000 is 48 mm. Find the actual distance between these monuments in km.
14. Unknown number
Determine the unknown number, which double of its fourth square is equal the fifth its square.
15. Vacation
Tomas spent 60% of his savings for his weekly vacation. He was 32 € left. How many euros did he have before vacation?
16. Rhombus
If we increase the rhombus side by 2.4 cm; its perimeter is 20 cm. How long was the side of the rhombus?
17. Rainfall
The annual average rainfall in India was in Cherrapunji in the year 1981 26 461 mm. How many hectoliters of water fell on 1 m2? Would fit this amount of water into a cube of three meters?
18. Tickets 3
A total of 645 tickets were sold for the school play. They were either adult tickets or student tickets. There were 55 fewer student tickets sold than adult tickets. How many adult tickets were sold?
19. Square s3
Calculate the diagonal of the square, where its area is 0.49 cm square. And also calculate its circumference.
20. Dividing
Divide the three line segment 13 cm, 26 cm and 19.5 cm long for parts so that the individual parts were equally long and longest. How long will the individual parts and how many it will?

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