edited by
669 views

1 Answer

1 votes
1 votes

First, we can draw the diagram.



We know that area of circle $ = \pi \times(\text{radius})^{2}$

Four circles are cut from the circular sheet, each has a radius $ = 5\;\text{cm}$

Area of cut out portion $ = 4 \times \pi \times(5)^{2} = 4 \times \pi \times25 = 100 \pi$

Area of uncut portion $ = $ Area of circular sheet $-$ Area of a cutout portion

$\qquad \qquad \qquad \qquad= \pi \times(20)^{2}-100 \pi = 400 \pi -100 \pi = 300 \pi $

$\therefore$ The ratio of the uncut to the cut portion $ = 300 \pi :100 \pi = 3:1$

Correct Answer $:\text{C}$

edited by
Answer:

Related questions

0 votes
0 votes
0 answers
1
go_editor asked Mar 11, 2020
468 views
Direction for questions: Answer the questions based on the following information.In a locality, there are five small cities: $\text{A, B, C, D}$ and $\text{E}$. The dista...
1 votes
1 votes
1 answer
2
go_editor asked Mar 11, 2020
671 views
If $\text{ABCD}$ is a square and $\text{BCE}$ is an equilateral triangle, what is the measure of $\angle \text{DEC}?$$15^{\circ}$$30^{\circ}$$20^{\circ}$$45^{\circ}$
1 votes
1 votes
1 answer
3
go_editor asked Mar 11, 2020
465 views
The points of intersection of three lines $2\text{X} + 3\text{Y} – 5 = 0, 5\text{X} – 7\text{Y} + 2 = 0$ and $9\text{X} – 5\text{Y} – 4= 0$form a triangleare on l...
1 votes
1 votes
1 answer
4
go_editor asked Mar 11, 2020
510 views
The figure shows a circle of diameter $\text{AB}$ and radius $6.5$ cm. If chord $\text{CA}$ is $5$ cm long, find the area of $\triangle \text{ABC}$ __________
1 votes
1 votes
1 answer
5
go_editor asked Mar 11, 2020
554 views
In $\triangle \text{ABC},\:\angle \text{B}$ is a right angle, $\text{AC} = 6$ cm, and $\text{D}$ is the mid-point of $\text{AC}$. The length of $\text{BD}$ is ___________...