When the length of each side of a square is tripled, the area of the

Question

Competition Mode Question

When the length of each side of a square is tripled, the area of the new square is 200 more square inches than the area of the original square. What is the length, in inches, of each side of the original square?

A. 4
B. 5
C. 10
D. 15
E. 20

old new
length a 3a
area a^2 9a^2

9a^2=a^2+200
on solving.,
a=5

Ans B

A. 4
B. 5
C. 10
D. 15
E. 20

GMATWhizTeam · Answer

Solution 
 • Let us assume that each side of the original square is a inch.
 o Area of the original square  = a^2  square inches
o Each side of the new square  = 3a  inches
  Area of the new square  = (3a)^2 = 9a^2  square inches.   
 • Now, the area of the new square is 200 more square inches than the area of the original square.
 o This means,  9a^2 = a^2 + 200 
  ⟹ 8a^2 = 200 
  ⟹ a^2 = 25 
  ⟹ a = 5  inches  
Thus, the correct answer is  Option B.

rajatchopra1994 · Answer

Explanation:

Let the side of original square is x, then other one will have 3x

(3x)^2 - x^2 = 200
8x^2 = 200
x^2 = 25
x = 5

IMO-B

RaghavKhanna · Answer

Side of original square = a
=> Area of original square = a^2

Side of new square = 3a
=> Area of new square = 9a^2

Now, 
9a^2 - a^2 = 200
=> 8a^2 = 200
=> a^2 = 25
=> a = 5

Answer: B

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Neha2404 · Answer

IMO-B

Given
Side of original square-l
Side of new square. -3l

Difference in area of new square and original square is -200
Area of square=l^2

200=(3l)^2-l^2
200=8l^2
l= 5 answer

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sambitspm · Answer

Kindly see the attachment.

Time: 1:09

The solution contains only the steps I took during exam mode for this question. 
IMO B

Anu5162 · Answer

Original side be x
Original area is x^2
New side is 3x and new area is 9x^2
New area = original area+ 200 sq inch

9x^2 = x^2 + 200
X is 5

Posted from my mobile device

v12345 · Answer

Let original side of square be s.
According to question, Side is tripled,
 3s * 3s = s^2 + 200 
=>  9s^2 = s^2 + 200 
=>  8s^2 = 200 
=>  s^2 = 25 
=>  s = 5 
As side can't be negative.

Thus OA is B

kawal27 · Answer

Let the length of each side of square is x
if we consider 4^2=16 as length, then increase length 12^2 is 144 , so increase length must be greater than 4 
 area of square = side^2
 
 15^2 - 5^2 = 200
225-25=200

ANS=B

MayankSingh · Answer

IMO B

Ratio of area = Initial Area / Final Area = x^2 / (3x)^2 = 1/9
A/Q, Let Initial area = K , Final Area = 9K
9K-K= 200
K= 200/8 = 100/4 = 25

K = (Side)^2 = 25
Side = 5 unit

B. 5

Abi1995 · Answer

Ans - B

Original length L, area = L^2
New length 3L, new area= (3L)^2= 9L^2

New A = A + 200
9L^2- L^2 = 200

L=5

Posted from my mobile device

YES750 · Answer

Answer B - 5
3a^2-a^2=200
a^2=25
a=5

monikakumar · Answer

When the length of each side of a square is tripled, the area of the new square is 200 more square inches than the area of the original square. What is the length, in inches, of each side of the original square?

A. 4
B. 5
C. 10
D. 15
E. 20

old new
length a 3a
area a^2 9a^2

9a^2=a^2+200
on solving.,
a=5

Ans B

A. 4
B. 5
C. 10
D. 15
E. 20

old new
length a 3a
area a^2 9a^2

9a^2=a^2+200
on solving.,
a=5

Ans B

When the length of each side of a square is tripled, the area of the

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When the length of each side of a square is tripled, the area of the

Prep Toolkit

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