The spray from a certain water sprinkler covers a circular region of l

Question

The spray from a certain water sprinkler covers a circular region of lawn \(25\pi\) square yards in area, with the sprinkler at the center. If the water pressure to the sprinkler is increased, so that the area covered by the sprinkler is increased by 300%, how far from the sprinkler does the spray reach?

(A) \(5\sqrt{3}\)

(B) 10

(C) 15

(D) \(10\sqrt{3}\)

(E) 20

(A)  5\sqrt{3}

(B) 10

(C) 15

(D)  10\sqrt{3}

(E) 20

parth2424 · Answer

B)
new area 100pi
R^2 = 100
R = 10

Posted from my mobile device

Mangs1297 · Answer

New Area = 25pi*4= 100pi

r=10

hence B) 10

Abhishek009 · Answer

New area is  \frac{(300+100)}{100}*25\pi  =  100\pi

We know area is  πr^2 = 100π

So,  r = 10 , Answer must be (B)

increased by 300% means to be multiplied by 4

parth2424 · Answer

Thanks for pointing that out

GCMEMBER · Answer

The spray from a certain water sprinkler covers a circular region of lawn \(25\pi\) square yards in area, with the sprinkler at the center. If the water pressure to the sprinkler is increased, so that the area covered by the sprinkler is increased by 300%, how far from the sprinkler does the spray reach?

(A) \(5\sqrt{3}\)

(B) 10

(C) 15

(D) \(10\sqrt{3}\)

(E) 20

Previously Area covered = 25π 
New area covered = 4*25π =100π

πr^2 = 100π
r = 10

Posted from my mobile device

EgmatQuantExpert · Answer

Solution 
  Given  
In this question, we are given that
 • Area of smaller circle = 25π
• Area covered by the sprinkler increased by 300%

To find  
We need to determine
 • The radius of the bigger circle

Approach and Working out  
 • Area of bigger circle = 25π + 3 x 25π = 100π
 o This implies,  πr^2 = 100π 
o Thus, r = 10

Hence, Option B is the correct answer.

Correct Answer: Option B

The spray from a certain water sprinkler covers a circular region of l

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The spray from a certain water sprinkler covers a circular region of l

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