# Examples for 7th grade (seventh)

1. Clocks
How long track travel the second hand in 46 hours, the end of which is 4 cm long.
2. The cylindrical container
The container has a cylindrical shape the base diameter 0.8 meters has a content area of the base is equal to the content area of the shell. How many full liters of water can be poured maximally into the container?
3. Pennies
800 pennies have the same value as 100 ducats. 100 pennies have the same value as 250 tolars. How many ducats has the same value as 100 tolars?
4. Fire tank
How deep is the fire tank with the dimensions of the bottom 7m and 12m, when filled with 420 m3 of water?
5. Bank deposit
Ms Jana after the withdraw amount of 2,500 euros after year saving in bank. What was her deposit if the interest rate was 2.5% p.a..
6. Tiles
The room has dimensions 12 m and 5.6 m. Determine the number of square tiles and their largest possible size to cover them room's floor.
7. Two workers
Two workers together execute some work in 10 days. The first worker would have done himself in 20 days. How many days would have done himself a second worker?
8. Stock
Enterprise sold 7/12 of their products to foreign markets and 2/5 of the remainder sold at home. How many % of the products is still in stock?
9. A family
A family of four pays for garbage collection per year 1800 Kč. How many crowns a year the waste company get from the house where lives 93 people?
10. Four-digit number
Find also a four-digit number, which quadrupled written backwards is the same number.
11. Three digits number 2
Find the number of all three-digit positive integers that can be put together from digits 1,2,3,4 and which are subject to the same time has the following conditions: on one positions is one of the numbers 1,3,4, on the place of hundreds 4 or 2.
12. angles in quadrilateral
What size have angles in quadrilateral (4-gon) if they are in a ratio of 8: 9: 10: 13?
13. Trapezium
The area of trapezium is 35cm2 find its altitude if the bases are 6cm and 8cm.
14. Calcium and citality
The daily dose of calcium obtained using 0.75 liters of milk and 60 grams of cheese. A/ At the morning I drank half a liter of milk. How much cheese I must eatto eat a daily dose of calcium? b / I ate 50 grams of cheese, how much milk I must drink? c /
15. Salt
1 t of sea water contains 25 kg of salt. How many tons of seawater must be evaporated to obtain 2 q of salt?
16. Class
The class has 18 students. Everyone knows inline skating or skateboarding. Inline skating can ride 11 students on a skateboard 10. How many ride on inline skates and on skateboard?
17. 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.
18. Sisters
Sisters Janka and Danka are saved together 220 CZK. On a trip to Janka wants to take a fifth of her savings and Danka quarter. Then they will have 50 CZK on the trip. How much money saved Janka and Danka?
19. Double-track
On double-track express met with a freight train. Express travel at speed 72 km/h, a freight train at speed 36 km/h. After what time period will be from 9 km apart?
20. Car rent
Rental cars are paid a fixed daily fee plus 16 cents for each kilometer traveled. Samuel want to rent a car for a day and worked out that will pay 175 euros. When paying he got a 20% discount on the daily fee, the cost per kilometer is unchanged. Samuel t

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