A circle is divided into four sections. If three sections constitute

Question

A circle is divided into four sections. If three sections constitute \(\frac{1}{4}\), \(\frac{2}{5}\) and \(\frac{3}{10}\) of its total area, respectively, what is the fractional value of the area of the fourth section?

A) 19/20

B) 16/19

C) 9/20

D) 1/10

E) 1/20

A) 19/20

B) 16/19

C) 9/20

D) 1/10

E) 1/20

globaldesi · Answer

total area is composed by 4 sections.
Thus area of remaining section =  1- ( \frac{1}{4} +\frac{2}{5}+\frac{3}{10}) 
 1-\frac{19}{20} 
 \frac{1}{20} 
E

EgmatQuantExpert · Answer

Solution

Given  
In this question, we are given that
 • A circle is divided into four sections
• Three sections constitute 1/4, 2/5 and 3/10 of its total area, respectively

To find  
We need to determine
 • The fractional value of the area of the fourth section

Approach and Working out  
Total proportion of area of the three sections =  \frac{1}{4} + \frac{2}{5} + \frac{3}{10} = \frac{5}{20} + \frac{8}{20} + \frac{6}{20} = \frac{19}{20} 
 • Remaining area =  1 – \frac{19}{20} = \frac{1}{20}

Thus, option E is the correct answer.

Correct Answer: Option E

Archit3110 · Answer

let total area of circle = 100 ; pi * r^2
so the three parts are covering ; 1/4* 100 ; 25 ; 2/5*100 ; 40 and 3/10 ; 30 
total covered area ; 25+40+30 ; 95
left 5 which is 5/100 ; 1/20 part
IMO E

pandajee · Answer

Another way of solving this problem is to convert the fraction to decimal (Do it only of you are good with decimals and you remember the common values of fractions like 1/2, 1/3, 1/4 etc..)

Area 1 = 1/4 = 0.25
Area 2 = 2/5 = 0.4
Area 3 = 3/10 = 0.3
Area of three sections= 0.25 + 0.4 +0.3 = 0.95

Fractional value of the area of the fourth section = 1 - (sum of other three areas) = 1 - 0.95 = 0.05 = 5 /100 = 1/ 20 
Hence, Ans is E Hit   KUDOS   if you learned another way of solving this problem.

felipehendrix · Answer

We need substract from the full circle the sections stated. For that we need to find the LCM

1-(1/4)-(2/5)-(3/10)= (20-5-8-6)/20 = 1/20

Answer is E

A circle is divided into four sections. If three sections constitute

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A circle is divided into four sections. If three sections constitute

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