# Examples for 7th grade (seventh) - page 12

1. Drunk man
Drunkman has 2.6‰ of alcohol in the blood. How many grams of alcohol has in blood, if he have 5 kg of blood?
2. Mouse Hryzka
Mouse Hryzka found 27 identical cubes of cheese. She first put in a large cube out of them and then waited for a while before the cheese cubes stuck together. Then from every wall of the big cube she will eats the middle cube. Then she also eats the cube
3. Day
What part of the day is 23 hours 22 minutes? Express as a decimal number.
4. Divisibility
Determine the smallest integer which divided 11 gives remainder 4 when divided 15 gives remainder 10 and when divided by 19 gives remainder 16.
5. Pumps
Pump that draws water at velocity 3.5 liters per second water from a construction trench take 35 minutes. a) Find out how many minutes the water would run out of the trench pump that draws 7.4 liters of water per second. b) What is the pumping velocity wo
6. Compass
What angle are between directions WSW (WestSouthWest) and SSE (SouthSouthEast) on the compass?
7. Ratio
Increase in the ratio 20:4 number 18.5.
8. AVG of INT
What is the average of the integers from 9 throuht 52 inclusive?
9. Pizza master
Master says that he can splits pizza to 16 parts by five equals straight cuts. Is it possible?
10. Lid
What is the weight of concrete cover (lid) to round shape well with a diameter 1.8 m, if the thickness of the cover is 11 cm? 1 m3 of concrete weighs 2190 kg.
11. Lines
Five bus lines runs at intervals 3, 6, 9, 12, 15 minutes. In the morning, suddenly start at 4:00. After how many minutes the bus lines meet again?
12. Fertilizer
Mr. Gherkin use for fertilization 8% solution of fertilizer. 4 liters of it still left. How much water must be added to the solution to make only 4% solution?
13. Pedestrian and cyclist
Pedestrian out with a speed of 4 km/hour from city center and after 1hour and 10 minutes came after him cyclist at speed of 18 km/h. At how many minutes he catches up with pedestrian?
14. Tiles
Hall has dimensions 325 &time; 170 dm. What is the largest size of square tiles that can be entire hall tiled and how many we need them?
15. Cyclist
A cyclist is moving at 35 km/h and follow pedestrian who is walking at speed 4 km/h. Walker has an advantage 19 km. How long take cyclist to catch up with him?
16. Water tank
Water tank shape cuboid has a width of 3.1 m and length twice larger. How high will reach water if water flow into 13 liters of water per second during 16 minutes?
17. Exhibition
The teacher paid for 280 Kč for 4.A students for admission to the exhibition. How many students were on the exhibition?
18. Hiker
Hiker went half of trip the first day, the third of trip the second day and remaines 15 km. How long trip he planned?
19. Train from Prague
First train from Prague started at 8:00 hour at 40 kilometers per hour. Train from Ostrava started at 9:20 at 80 km per hour. In how many hours and how far from cities with trains meet if the distance of cities is 400 km.
20. Two workers
The first worker completed the task by himself in 9 hours, the second in 15 hours. After two hours of joint work left first worker to a doctor and the second finished the job himself. How many hours worked second worker himself?

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