# Examples for 9th grade - page 40

1. Wind drift
The plane flies at 860 km/h, passing distance 3000 kilometers with the wind and once again against the wind for 6 h 59 min. What is the wind speed?
2. Aircrafts
Above the town hall tower flew the plane with constant speed 592 km/h and 15 minutes later the second plane at speed of 675 km/h. How long and how far from the town hall will be aircrafts caught up?
3. Combinatorics
The city has 7 fountains. Works only 6. How many options are there that can squirt ?
4. Meridian
What is the distance (length) the Earth's meridian 23° when the radius of the Earth is 6370 km?
5. Bottles of juice
How many 2-liter bottles of juice need to buy if you want to transfer juice to 50 pitchers rotary cone shape with a diameter of 24 cm and base side length of 1.5 dm.
6. Sequence 2
Write the first 5 members of an arithmetic sequence a11=-14, d=-1
7. Elevator
In homes with more floor elevators are used. For passenger transport, the most commonly used traction elevator counterweight. The top of the shaft engine room with the engine. The car is suspended on a rope, which is guided up over two pulleys to the count
8. Diagonal 20
Diagonal pathway for the rectangular town plaza whose length is 20 m longer than the width. if the pathway is 20 m shorter than twice the width. How long should the pathway be?
9. Garage
There are two laths in the garage opposite one another: one 2 meters long and the second 3 meters long. They fall against each other and stay against the opposite walls of the garage and both laths cross 70 cm above the garage floor. How wide is the garag
10. Vertices of RT
Show that the points P1 (5,0), P2 (2,1) & P3 (4,7) are the vertices of a right triangle.
11. Cars motion
From point A car start at the speed of 90 km/h. Against it departs from the point B at the same time another car at 60 km/h. For how long and where they met if the distance between A and B is 180 km?
12. Water level
The glass container has a cuboid shape with dimensions of the bottom 24 cm and 12 cm. The height of water is 26 cm. Calculate the volume of the body, which are sunk into the water if the water level rise by 3 cm.
13. Slope
Calculate the slope of a line that intersects points (-84,41) and (-76,-32).
14. RT leg and perimeter
Calculate the length of the sides of a right triangle ABC with hypotenuse c when the length of a leg a= 84 and perimeter of the triangle o = 269.
15. 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..
16. Max - cone
From the iron bar (shape = prism) with dimensions 6.2 cm, 10 cm, 6.2 cm must be produced the greatest cone. a) Calculate cone volume. b) Calculate the waste.
17. Wood
Wood contains 12% water. 1 m3 of wood weighs 650 kg. How many liters of water it contains?
18. The dam
The water reservoir is filled with first tributary for 25 hours second tributary for 35 hours. Some time were both inlets open, then a second tributary closed and the tank was filled in four hours. What time water flowed from both tributaries? (Expressed i
19. 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?
20. Lamp cone
Calculate the surface of a lamp shade shaped of a rotary truncated cone with base diameter 32 cm and 12 cm and height 24 cm.

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