# Examples for 9th grade - page 40

- Golden ratio

Divide line of length 14 cm into two sections that the ratio of shorter to greater is same as ratio of greater section to whole length of the line. - Mr Novak

Mr Novak earns an average 1249 euros. When increasing the salary they gave him a choice: ? What is better choice for Mr Novak? - Nuts

How many we must have at least nuts if we can equally divide it to 10 children, 11 children or 19 children and any nut left? - Cups

We have three cups. In the cups we had fluid and boredom we started to shed. 1 We shed one-third of the fluid from the second glass into the first and third. 2 Then we shed one quarter cup of liquid from the first to the second and to the third. 3 Then - Ski lessons

On the ski course leaves 80 pupils. They live in triple and quadruple rooms. Count if rooms is the 23. How many are triple and quadruple rooms? - Tetrahedral prism

The height of a regular tetrahedral prism is three times greater than the length of the base edge. Calculate the length of the base edge, if you know that the prism volume is 2187 cm^{3}. - 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? - Three-digit

How many three-digit natural numbers is greater than 321 if no digit in number repeated? - 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? - Meridian

What is the distance (length) the Earth's meridian 23° when the radius of the Earth is 6370 km? - Prism

The volume of tetrahedral prism is 2.43 m^{3}. Base of prism is a parallelogram in which a side 2,5dm and height ha = 18cm. Calculate the height of the prism. - 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. - Sequence 2

Write the first 5 members of an arithmetic sequence a_{11}=-14, d=-1 - Inflow - outflow

The tank will fill by inflow for 143 minutes and empties by outflow for 150 minutes. How long take to fill tank if it is also opened the inflow and outflow? - Combinatorics

The city has 7 fountains. Works only 6. How many options are there that can squirt ? - 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? - Percentage of waste

In a square plate with side 75 cm we cut 4 same circles. Calculate the percentage of waste. - 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 - 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. - 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?

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