# Examples for 7th grade (seventh) - page 23

1. Knight
Knight passed 13 km long track in 26 minutes, what was his average speed?
2. Czech crown salary
The monthly salary of the employee is CZK 10,800. In the course of the year the bulk salary increased by CZK 500. Calculate which month (1 ... 12) was increased if its annual income was 133,600 CZK.
3. Garden
Rectangular garden has a length 99 m and width 84 m. Calculate how many m2 will decrease its area if land by ornamental fence with width 30 cm.
4. Brothers and sisters
Lenka has as many brothers as sisters. Her brothers have twice as many sisters as brothers. How many brothers and sisters are in the family?
5. Diagonal
Can a rhombus have the same length diagonal and side?
6. Clock hands
The hands on the clock shows the time 12 hours and 2 minutes. Calculate the size of a sharp angle between clock hands three hours later.
7. Unknown number
Samuel wrote unknown number. Then he had add 200000 to the number and the result multiply by three. When it calculated he was surprised, because the result would have received anyway, if write digit to the end of original number. Find unknown number.
8. Cylinder - h2
Cylinder volume is 2.6 liters. Base area is 1.3 dm2. Calculate the height of the cylinder.
9. Pedestrian and the cyclist
Pedestrian and cyclist went against each from the two cities that are distant 40 km. Pedestrian started 30 minutes before the cyclist and walk an average speed of 5 km/h. What speed went cyclist when met after 120 minutes from the start of the pedestrian?
10. Square
If we increase one side of square by its one-half then square perimeter increase by 10 cm. What is the side of the square?
11. Scale
Cylinder was drawn in scale 2:1. How many times is the volume of the cylinder smaller in reality?
12. Peleton
Cycling race was run at an average speed of 45 km/h. One cyclist lost with defect 8 minutes. How long and how far he must go at speed 51 km/h to catch peleton again?
13. Simple interest
Peter put into bank 790 euros deposit. After 2 years on account overall was 974 euro. What was the interest rate if bank add simple interest?
14. Sports games
Pupils of same school participated district sports games. When dividing into teams found that in the case of the creation teams with 4 pupils remaining 1 pupil, in the case of a five-member teams remaining 2 pupils and in the case of six-members teams r
15. Tree trunk
Calculate the average tree trunk with a circumference of 149 cm.
16. 4-gon
It is true that a 4-gon whose two sides are parallel and the other two has equal length, is a parallelogram?
17. Annulus
Two concentric circles form an annulus of width 10 cm. The radius of the smaller circle is 20 cm. Calculate the content area of annulus.
18. 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 th
19. Square and circle
Into square is inscribed circle with diameter 10 cm.What is difference between circumference square and circle?
20. Trapezium
Determine the height of the trapezium ABCD, which has area 77.5 cm2 and base lengths 16 cm and 15 cm.

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