![The radius of a circle is 20 cm. If the radius of this circle is decreased to 10 cm, then by what percentage will the area of the circle decrease?](https://www.gkseries.com/blog/wp-content/uploads/2023/06/The-radius-of-a-circle-is-20-cm.-If-the-radius-of-this-circle-is-decreased-to-10-cm-then-by-what-percentage-will-the-area-of-the-circle-decrease.jpg)
Question | The radius of a circle is 20 cm. If the radius of this circle is decreased to 10 cm, then by what percentage will the area of the circle decrease? | |
Type | multiple_choice | |
Option | 60% | incorrect |
Option | 75% | correct |
Option | 35% | incorrect |
Option | 50% | incorrect |
Solution : percentage ratio =
![](https://www.gkseries.com/blog/wp-content/uploads/2023/06/image-546.png)
Required percentage =
![](https://www.gkseries.com/blog/wp-content/uploads/2023/06/image-547.png)