# Examples of area of plane shapes - page 13

1. Tiles
How many 46 cm square tiles will cover a floor 22.08 m by 8.74 m?
2. Silo
Outer perimeter of silo is 32 m. Concrete wall is 35 cm thick. What is diameter and area of inside floor of silo?
3. RT 10
Area of right triangle is 84 cm2 and one of its cathethus is a=10 cm. Calculate perimeter of the triangle ABC.
4. Ratio - rectangle
The rectangle has dimensions 6 cm and 9 cm. How many times increases area and its perimeter, when its dimensions increase in the ratio 5:3?
5. Sails
We known heights 220, 165 and 132 of sail. It has triangular shape. What is the surface of the sail?
6. Bathroom
How many CZK we pay for lining the perimeter walls of the bathroom with rectangular shape with dimensions 3.5 m and 4 m, high 1.5 m if 1 square m tile cost 300 CZK?
7. Center of gravity
In the isosceles triangle ABC is the ratio of the lengths of AB and the height to AB 10:12. The arm has a length of 26 cm. If the center of gravity T of triangle ABC find area of triangle ABT.
8. 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?
9. Trapezoid thirds
The ABCD trapezoid with the parallel sides of the AB and the CD and the E point of the AB side if the segment DE divides the trapezoid into two parts with the same area. Find the length of the AE line segment.
10. Rectangles - sides
One side of the rectangle is 10 cm longer than second. Shortens longer side by 6 cm and extend shorter by 14 cm increases the area of the rectangle by 130 cm2. What are the dimensions of the original rectangle?
11. Hexa prism
Determine the volume of hex prism with edge base 4 cm. The body height is 28 cm.
12. Area of RT 2
Calculate the area of right triangle whose legs have a length 5.8 cm and 5.8 cm.
13. Equilateral triangle v2
Equilateral triangle has a perimeter 36 dm. What is its area?
14. Circle inscribed
Calculate the perimeter and area of a circle inscribed in a triangle measuring 3 , 4 and 5 cm.
15. Square vs rectangle
Square and rectangle have the same area contents. The length of the rectangle is 9 greater and width 6 less than side of the square. Calculate the side of a square.
16. Rectangular trapezium
Calculate the perimeter of a rectangular trapezium when its content area is 576 cm2 and sice a (base) is 30 cm, height 24 cm.
17. 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?
18. Right angled
From the right triangle with legs 12 cm and 20 cm we built a square with the same content as the triangle. How long will be side of the square?
19. Sides of the triangle
Calculate triangle sides where its area is S = 84 cm2 and a = x, b = x + 1, xc = x + 2
20. Pavilion
The rectangular pavilion with dimensions 3.5 m and 2.75 m to be paved with square tiles of side 25 cm price of CZK 22 per 1 piece or rectangular tiles with sides of 20 cm and 15 cm in the price of CZK 11 per 1 pc. Which solution is cheaper (write its price

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