• recategorized by
1,612 views
–1 –1 vote

From a circular sheet of paper with a radius of 20 cm, four circles of radius 5cm each are cut out. What is the ratio of the paper left to the area of the circles?

  1. $1:3$ 
  2. $4:1$ 
  3. $3:1$
  4. $4:3$

1 Answer

0 0 votes

Area of the circular sheet = $\pi$ * (20)2 = 400 $\pi$

Area of 4 smaller circles cut out = 4 * $\pi$ * (5)2 = 100 $\pi$

So, area of remaining paper = 300 $\pi$

$\therefore$ Ratio of the paper left to the area of the circles = 300 $\pi$ : 100 $\pi$ = 3 : 1

C is the answer.

 

Position:
Show:

Related questions

2 2 votes
2 2 answers
3.0k
3.0k views
Misbah Ghaya asked Jul 20, 2017
3,039 views
The amount of money invested (in rupees crore) in the core infrastructure areas of two districts, Chittoor and Khammam, Andhra Pradesh as follows:If the total investment ...
2 2 votes
1 1 answer
2.8k
2.8k views
Misbah Ghaya asked Jul 20, 2017
2,830 views
The amount of money invested (in rupees crore) in the core infrastructure areas of two districts, Chittoor and Khammam, Andhra Pradesh as follows:In Khammam district the ...
2 2 votes
1 1 answer
2.3k
2.3k views
Misbah Ghaya asked Jul 20, 2017
2,255 views
The amount of money invested (in rupees crore) in the core infrastructure areas of two districts, Chittoor and Khammam, Andhra Pradesh as follows:The investment in Electr...
2 2 votes
1 1 answer
2.6k
2.6k views
Misbah Ghaya asked Jul 20, 2017
2,563 views
The amount of money invested (in rupees crore) in the core infrastructure areas of two districts, Chittoor and Khammam, Andhra Pradesh as follows:Approximately how many t...
2 2 votes
2 2 answers
2.8k
2.8k views
Misbah Ghaya asked Jul 20, 2017
2,843 views
The amount of money invested (in rupees crore) in the core infrastructure areas of two districts, Chittoor and Khammam, Andhra Pradesh as follows:By what percent was the ...