# Examples for 7th grade (seventh) - page 32

1. Buses
Buses Ikarus and Karosa simultaneously started at 8:00 from the final station. Ikarus is returned to the station after 30 minutes. Karosa after 45 minutes. At what time both buses again returned to the station?
2. Container with water
The weight of a container with water is 2.48 kg. If the cast 75% water, the container with water has a weight of 0.98 kg. Determine the weight of the empty container. How much water was originally in the container?
3. Chess
How many different ways can initiate a game of chess (first pass)?
4. Bathroom
How many CZK we pay for lining the perimeter walls of the bathroom with rectangular shape with dimensions 3.5 m and 4 m, high 1.5 m if 1 square m tile cost 300 CZK?
5. Pool 3
How long will fill pool cuboid shape (8m 6m 1.5m) when flows 15 liters/s?
6. College
At the college are at 57 rooms 194 students. Some rooms are triple and some quad. How many triple and quadruple rooms there is, if it is all fully occupied?
7. Rings groups
27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
8. Plums
In the bag was to total 136 plums. Igor took 3 plums and Mary took 4/7 from the rest. How many plums remained in the bag?
9. Colors
Willie got birthday 6 colour pens in different colors. How many ways he can give them side by side in pencil?
10. RWY
Calculate the opposite direction of the runway 13. Runways are named by a number between 01 and 36, which is generally one tenth of the azimuth of the runway's heading in degrees: a runway numbered 09 points east (90°), runway 18 is south (180°), runway.
11. Pumps
First pump flows 16 liters per second into the basin by the second pump 75% of the first and by third pump half more than the second. How long will take fill basin by all three pumps simultaneously volume 15 m3 (cubic meters)?
12. Right triangle - leg
Calculate to the nearest tenth cm length of leg in right-angled triangle with hypotenuse length 9 cm and 7 cm long leg.
13. Jumps
At least how many jumps must do frog to overcome the distance of 7 meters? Jump of frog is 18 cm long.
14. Painters
One painter could paint a school for 7 days. The second one for 6 days. It was necessary to paint the school in two days. Next painter was invited and all worked together. How long would this painter painted the school itself?
15. Great Wall of China
Great Wall of China is long 8880 km. Historically valuable however is only 30% of its length. What amount of insurance pays the Peoples Republic of China a month for this monument, if the insurance company charges \$ 10 per year per kilometer of historic s
16. Students
The class has 22 students. 2 of which has assesement of 2. Count of assesement of 1 is three times more than count of students with assesement of 3. How many students has assesement of 1 and how many students has assesement of 1.
17. Mukls
The working group, in which 6 workers would ordered job completed within 21 working days. How many workers must be accept yet that the contract will be completed in 14 working days?
18. Average
The arithmetic mean of the two numbers is 71.7. One number is 5. Calculate the second number.
19. Soup
47% of pupils at the school to eat in the canteen, 1/47 of students who eat in the canteen eat lunch soup. a) What percentage of pupils who eat in the canteen and eat soup for lunch? b) What percentage of all pupils of school eat lunch soup?
20. Yogurt
The board is 35 yogurts. How many boards of yogurts must be ordered for 886 people in the canteen?

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