The figure below is made up of a quadrant and a circle overlapping each other. The quadrant touches the circle at points F and G.
The circle, with centre O, has a diameter of 24 cm. Find the area of the shaded parts.
(Take π=3.14\pi = 3.14)

Work through it with AI →

It won't just hand you the answer — it asks where you're stuck.How the checker works

Worked solution

15

1. Find the area of the circle and the quadrant.

Radius of the circle, r=24÷2=12 cmr = 24 \div 2 = 12\text{ cm}.
Area of the circle =πr2=3.14×122=452.16 cm2= \pi r^2 = 3.14 \times 12^2 = 452.16\text{ cm}^2.
Radius of the quadrant, R=24 cmR = 24\text{ cm}.
Area of the quadrant =14πR2=14×3.14×242=452.16 cm2= \frac{1}{4} \pi R^2 = \frac{1}{4} \times 3.14 \times 24^2 = 452.16\text{ cm}^2.

2. Determine the area of the overlapping region.

The straight edges of the quadrant form a 90∘90^\circ angle at G. Since the angle in a semicircle is 90∘90^\circ, these edges pass exactly through the ends of the horizontal diameter of the circle.
The overlapping region consists of the upper semicircle and the triangle formed by the horizontal diameter and point G.
Area of upper semicircle =452.16÷2=226.08 cm2= 452.16 \div 2 = 226.08\text{ cm}^2.
Area of triangle =12×base×height=12×24×12=144 cm2= \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 24 \times 12 = 144\text{ cm}^2.
Total overlap area =226.08+144=370.08 cm2= 226.08 + 144 = 370.08\text{ cm}^2.

3. Calculate the total area of the shaded parts.

The shaded parts are the regions in the quadrant outside the circle, and the regions in the circle outside the quadrant.
Shaded area =(Area of quadrant−Overlap)+(Area of circle−Overlap)= (\text{Area of quadrant} - \text{Overlap}) + (\text{Area of circle} - \text{Overlap})
Shaded area =(452.16−370.08)+(452.16−370.08)=82.08+82.08=164.16 cm2= (452.16 - 370.08) + (452.16 - 370.08) = 82.08 + 82.08 = 164.16\text{ cm}^2.

Answer

164.16 cm2164.16\text{ cm}^2

AI analysis — may contain mistakes.

Worked this one out on paper? Snap your steps and Gigle's AI math checker will circle the step where it went wrong.

More questions on this topic

  1. 1定积分∫01(2x−x2)dx\int_{0}^{1}(\sqrt{2x{-}x^{2}})dx等于()({ }) A. π4\dfrac{\pi}{4} B. π2\dfrac{\pi}{2} C. π−14\dfrac{\pi{-}1}{4}…
  2. 2The figure is made up of a rectangle, a square and a quadrant. Find the area of the shaded part. (Take π=3.14\pi = 3.14) Ans…
  3. 3用同样长的绳子分别围长方形、正方形、圆,面积从小到大的排列是()(\quad) A. 圆<<正方形<<长方形 B. 正方形<<长方形<<圆 C. 圆>>正方形>>长方形 D. 长方形<<正方形<<…
  4. 4用44米长的绳子把一只羊拴在一根木桩上,这只羊吃草面积最大是()(\quad)平方米。 A. 4×2×3.144×2×3.14 B. 4×4×3.144×4×3.14 C. 3.14×23.14×2 D. 2×42×4
  5. 5一张长方形的纸,它的长是8厘米,宽是6厘米.(1)如果用它剪下一个最大的圆后,剩下的面积是多少平方厘米?(2)如果用它剪下一个最大的半圆,剩下的面积是多少平方厘米?