# Grade - examples - page 206

1. KLM triangle
Find the length of the sides of the triangle KLM if m = 5cm height to m = 4.5 cm and size MKL angle is 70 degrees.
2. Decorative fence
The rectangular garden is 57 m long and 42 m wide. Calculate how much m² it will reduce if it encloses with a 60 cm wide decorative fence.
3. Constant motion
The car has undergone constant motion 120 km in 1 hour 30 minutes. Determine its average speed. Determine how long car drove in the first 20 minutes and 50 minutes from the start of the move.
4. Ruler and compass
Use a ruler and compass to construct a triangle ABC with AB 5cm BAC 60° and ACB 45°.
5. The aquarium
The aquarium has a capacity of 18 liters. What is its height when the square bottom is 8 2/3 cm long?
6. Two thirds
Find two-thirds of the number equal to two-thirds of 99
At a weather centre, the temperature at midnight was -2 degree Celsius and by noon it had raised 4 degree Celsius. What is the new temperature?
8. Employees
There are 1116 people working in three factory halls. In the first one, there are 18% more than the third, and 60 persons more than the second. How many employees work in individual halls?
9. Game 27
Susan wanted to play the game. In the beginning, the first says a number from 1 to 8. Then the second player adds a number from 1 to 5 and tells the sum. Again, the Susan adds a number from 1-5 and say sum and etc. . . The winner must say the number 27. Wh
10. Free fall
The free fall body has gone 10m in the last 0.5s. Find the body speed at the moment of impact.
11. Ophelia
Ophelia recorded the temperature of a cold store every two hours. 1. At 6am it was -4°C and at 8am it was -1°C. By how much did the temperature rise? 2. The temperature went up by 5°C in the next two hours. .What was the temperature at 10am?
12. Brick weight
Half the weight of a brick plus 20 pounds is equal to 1/3 the weight of the brick plus 30 pounds. How much does the brick weigh?
13. Two gears
The two gears fit together. The larger gear has 32 teeth, the smaller has 20 teeth less. How many times does turn a smaller gear if the bigger gear turns three times?
14. Three brothers
The three brothers have a total of 42 years. Jan is five years younger than Peter and Peter is 2 years younger than Michael. How many years has each of them?
15. Bricklayer
How much do we pay for a bricklayer laying a pavement in a square room with a diagonal of 8 m, if 1 sqm with work will cost for CZK 420?
16. Circle annulus
There are 2 concentric circles in the figure. Chord of larger circle 10 cm long is tangent to the smaller circle. What are does annulus have?
17. Negative in equation
2x + 3 + 7x = – 24, what is the value of x?
18. A boy
A boy of height 1.7m is standing 30m away from flag staff on the same level ground . He observes that the angle of deviation of the top of flag staff is 30 degree. Calculate the height of flag staff.
19. Std-deviation
Calculate standard deviation for file: 63,65,68,69,69,72,75,76,77,79,79,80,82,83,84,88,90
20. Half-sphere roof
The roof above the castle tower has the shape of a 12.8 m diameter half-sphere. What is the cost of this roof, if the cost of 1 square meter is 12 euros and 40 cents?

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