Aptitude - Area - Discussion
Discussion Forum : Area - General Questions (Q.No. 2)
2.
An error 2% in excess is made while measuring the side of a square. The percentage of error in the calculated area of the square is:
Answer: Option
Explanation:
100 cm is read as 102 cm.
A1 = (100 x 100) cm2 and A2 (102 x 102) cm2.
(A2 - A1) = [(102)2 - (100)2]
= (102 + 100) x (102 - 100)
= 404 cm2.
| Percentage error = |
 |
404 | x 100 |  % |
= 4.04% |
| 100 x 100 |
Discussion:
40 comments Page 3 of 4.
Bhavana said:
1 decade ago
Why are we taking 100 for this sum when it is not mentioned in the question. Please explain?
Aditi said:
1 decade ago
Why are we taking 100 for this sum when it is not mentioned in the question. Please explain?
Nitin said:
1 decade ago
%error = a+b+ab/100.
a and b are +ve and -ve as per increment and decrement respectively.
a and b are +ve and -ve as per increment and decrement respectively.
Shikha said:
1 decade ago
Why are we dividing 401 by 100 two times and not one time?
Why it is not- (401*100) /100?
Why it is not- (401*100) /100?
Meghna said:
1 decade ago
@anbu.
Take the formula a^2-b^2
which is equal to (a+b)(a-b) ... so (102-100)(102+100)
Take the formula a^2-b^2
which is equal to (a+b)(a-b) ... so (102-100)(102+100)
HARSHAVARDHAN REDDY said:
6 years ago
Use the formula {A+B+(AB/100)}.
Here A=2 for side.
For area A=B.
2+2+2*2/100=4.04.
Here A=2 for side.
For area A=B.
2+2+2*2/100=4.04.
(1)
Sakshi said:
1 decade ago
We can also get the percentage by this.
Percentage error = 404/100 = 4.04
Percentage error = 404/100 = 4.04
Tejasri samala said:
6 years ago
In order to find the percentage error, the formula is [ (x*x) /100+2*x]%.
Raju said:
9 years ago
The formula X + Y + (X * Y/100) is the best for square and rectangle.
Ramesh said:
1 decade ago
Sir Percentage error is not understanding. Please solve the answer.
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