# Examples for 9th grade - page 45

- Chimney

Lower circumference of of the chimney is 12.57 m, top circumference is 5.655 m. The slope of the walls is 87°. Determine the height of the chimney. - Painters

One painter could paint a school for 7 days. The second one for 6 days. It was necessary to paint the school in two days. Next painter was invited and all worked together. How long would this painter painted the school itself? - Area of the cone

Calculate the surface area of the cone, you know the base diameter 25 cm and a height 40 cm. - Rectangles - sides

One side of the rectangle is 25 cm longer than second. Shortens longer side by 14 cm and extend shorter by 13 cm increases the area of the rectangle by 130 cm^{2.}What are the dimensions of the original rectangle? - Candies

In the box are 12 candies that look the same. Three of them are filled with nougat, five by nuts, four by cream. At least how many candies must Ivan choose to satisfy itself that the selection of two with the same filling? ? - Quadratic equation

Determine the numbers b, c that the numbers x_{1}= -7 and x_{2}= -4 were roots of quadratic equation: ? - Teams

How many ways can divide 12 players into two teams of 6 member? - Three piles

100 kg of sugar we divide into three piles. The first pile is small. If we added to second 2 kg of sugar it would have 25% more sugar than the first pile. If we added to third pile 3 kg of sugar it would have 20% more sugar than the 2nd pile. How many kil - Perimeter of triangle

In triangle ABC angle A is 60° angle B is 90° side size c is 15 cm. Calculate the triangle circumference. - Cyclist

Cyclist rode two-fifths of the way the first day. The second day drove 5 km less while traveled three-eighths of route. How many kilometers does he have to finish target? - Equilateral triangle v2

Equilateral triangle has a perimeter 36 dm. What is its area? - Polygon 42

Which polygon has 42 more diagonals than sides? - Glass

How many glass are needed to produce glass with base regular 5-gon if one base triangle in the base is 4.2 square cm and the height is 10 cm? - Seamstress

Seamstress bought two kinds of textile together 25 meters. One at 50 SKK and the second 70 SKK per meter. How many meter bought from this two textiles when paid totally 1540 SKK? - Cuboid - complicatef

Three walls of the same cuboid has content 6 cm^{2,}10 cm^{2}and 15 cm^{2.}Calculate the volume of the cuboid. - Rings groups

27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups? - 10 pieces

How to divide the circle into 10 parts (geometrically)? - Apples

A 2 kg of apples cost a certain sum of money. This sum is equal to the amount of kilograms for which we pay 72 CZK. How much is 1 kg of apples? - Crowns

1180 crowns is divided into three people that A got 20% less than B and C by 15% more than B. How many got A,B and C? - Silver medal

To circular silver medal with a diameter of 10 cm is inscribed gold cross, which consists of five equal squares. What is the content area of silver part?

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