# Examples for 7th grade (seventh) - page 44

1. Surface area
Calculate the surface area of a four-sides 2-m high prism which base is a rectangle with sides 17 cm and 1.3 dm
2. Water reservoir
The water tank has a cuboid with edges a= 1 m, b=2 m , c = 1 m. Calculate how many centimeters of water level falls, if we fill fifteen 12 liters cans.
3. Rectangle from string
String 12m. Make rectangle when one side is two times longer than its width.
4. Tank
The tank bottom has dimensions of 1.5 m and 3 2/6 m. The tank is 459.1 hl of water. How high is the water surface?
5. Rhumbline
Find circumference and area of the rhumbline ABCD if the short side AD of which has a length of 5 cm, and the heel of the height from D leading to the AB side divides the AB side into two sections of 3 cm and 4 cm.
6. Matches
George poured out of the box matches and composing them triangles and no match was left. Then he tries squares, hexagons and octagons and no match was left. How many matches must be at least in the box?
7. Journey to grandma
Daniel traveled to grandma. He travel 100 km along. Halfway travel by train, one quarter by bus, one tenth by the bicycle and the rest travel by car. How many km travel km by car?
8. Ferris wheel
Ferris wheel reaches to 22 m tall and moves at the speed of 0.5m/s. During one drive wheel rotates three times. What is the total drive time?
9. Percentages
Expressed as a percentage:
10. Driving school
Driving final exam involving 10 attendants. The exam consists of three parts. 2 fails at test (quiz) and 6 students fails on car skills test on playground (slalom between the cone). The practical part of the test - driving in town in the real traffic - al
11. Tram
In the three-part tram went 206 passengers in front of others, 226 after others and in the middle half of all. How many passengers went in tram total?
12. New refrigerator
New refrigerator sells for 1024 USD, Monday will be 25% discount. How much USD will save, and what will be the price?
13. Pupils at cinema
Alena bought movie tickets for two groups of pupils. The first group purchased 7 tickets for 1st and 5 tickets for 2nd place and she pay 62Kč. For the second group bought 11 tickets for 1st and 4 tickets for 2nd place and pay 82Kč. How much was the ticket
14. Goods
To the market is introducing a new product, the first week is sold at a reduced price. 8 products is sell at an entry price same as 5 products at the normal price. How much % is reduced price less than the current price for this product?
15. Force meter
We put the statuette on the force meter. The force meter showed a value 25 N. Then we placed the statuette on the force meter completely immersed in the water. The force meter showed a value 17 N. What is the volume of the statuette?
16. Dressmaker
Dressmaker left a piece of canvas shorter than 5 meters. She is deciding whether it sew a skirt or dress. The canvas was exactly as much as they consumed had cut up her skirt to 120 cm, or 180 centimeters dress. What a piece of canvas left her?
17. Table 3x3
Table with numbers 3x3 in the first row 66,24,33 in the second row 57,? 19 in the third row 18,45,60 What number comes ar mark ?. Maybe the numbers: 22,46,45,47
18. Roses
On the large rosary was a third white, half red, yellow quarter and six pink. How many roses was in the rosary?
19. The classroom
In the seventh class the number of boys and girls are at a ratio of 4:5. Boys are 16. How many total students are in the classroom?
20. Wheel
Diameter of motocycle wheel is 52 cm. How many times rotates wheel on roand long 2 km?

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