Practice problems of the area of a circle
Number of problems found: 170
- The crane
The construction crane has a 20m long arm. What area of construction in ares can it handle from this crane if it rotates around its axis?
- Coat of arms
The class created its own coat of arms, which had a shape composed of an isosceles trapezoid ABCD (shorter base is a = 4.5 cm long, longer 2a = 9 cm, trapezoid height 6 cm) and a semicircle with center S and diameter AB. The trapezoid was formed by three
- The formula
The formula for the area of a circle is (Pi x r x r) where r = measure of the radius and Pi = 3.14. What is the area of a circle whose radius measures 1 cm?
- The ratio
The ratio of the lengths of the two circles is 5: 2. Find the ratio of a a) the radii of these circles b) the areas for these circles
- Circle segment
A quarter circle with radius 4 has the same content as a circle segment with radius 3. What is the magnitude of the center angle of the circle segment?
- Circle inscribed
There is a triangle ABC and a circle inscribed in this triangle with radius 15. The point T is the point of contact of the inscribed circle with the side BC. What is the area of the triangle ABC if | BT | = 25 a | TC | = 26?
The ornament consists of one square and four dark semicircles. The area of the square is 4 cm ^ 2. Find the area of one dark semicircle and round the result to hundreds.
Find the area of a regular dodecagon (n=12) if the radius of the circumscribed circle is 5 cm.
- The collar
The collar on the dress has the shape of an annulus 6 cm wide. The circumference of the inner circle is 31.4 cm. How much cm² of fabric is needed to make one collar?
Megapizza will be divided among 100 people. First gets 1%, 2nd 2% of the remainder, 3rd 3% of the remainder, etc. Last 100th 100% of the remainder. Which person got the biggest portion?
- Metal washers
Metal washers with a diameter of 80 mm are cut from a strip of steel sheet with a width of 10 cm and a length of 2 m. Calculate the percentage of material waste if no material is lost when two adjacent circles meet.
- Round skirt
The cut on the round skirt has the shape of an annulus. Determine how much m² of fabric will be consumed on an 80 cm long skirt. The circumference of the waist is a circle with a smaller radius and is 69 cm.
- Right triangle
A circle with a radius of 5 cm is described in a right triangle with a 6 cm leg. What is the height at the hypotenuse of this triangle?
- Ratio of squares
A circle is given in which a square is inscribed. The smaller square is inscribed in a circular arc formed by the side of the square and the arc of the circle. What is the ratio of the areas of the large and small squares?
- Square and circles
The square in the picture has a side length of a = 20 cm. Circular arcs have centers at the vertices of the square. Calculate the areas of the colored unit. Express area using side a.
Calculate the content of a regular 15-sides polygon inscribed in a circle with radius r = 4. Express the result to two decimal places.
We describe a circle of the square, and we describe a semicircle above each side of the square. This created 4 flakes. Which is bigger: the area of the central square, or the area of four flakes?
- Annulus from triangle
Calculate the content of the area bounded by a circle circumscribed and a circle inscribed by a triangle with sides a = 25mm, b = 29mm, c = 36mm
- Perimeter of the circle
Calculate the perimeter of the circle in dm, whose radius equals the side of the square containing 0.49 dm²?
- Eq triangle minus arcs
In an equilateral triangle with a 2cm side, the arcs of three circles are drawn from the centers at the vertices and radii 1cm. Calculate the content of the shaded part - a formation that makes up the difference between the triangle area and circular cuts
Circle practice problems. Examples of area of plane shapes.