Aptitude - Percentage - Discussion
Discussion Forum : Percentage - General Questions (Q.No. 9)
9.
| A student multiplied a number by | 3 | instead of | 5 | . |
| 5 | 3 |
What is the percentage error in the calculation?
Answer: Option
Explanation:
Let the number be x.
| Then, error = | 5 | x - | 3 | x = | 16 | x. |
| 3 | 5 | 15 |
| Error% = |  |
16x | x | 3 | x 100 |  % = 64%. |
| 15 | 5x |
Discussion:
134 comments Page 11 of 14.
Sid toons said:
1 decade ago
Let the number be 300. Then 300* (3/5) = 180. And 300* (5/3) =500.
500-180 = 320 Now for checking percentage error,
320/500 * 100 = 64%.
500-180 = 320 Now for checking percentage error,
320/500 * 100 = 64%.
Kondareddy said:
1 decade ago
So simple friends,
First find error.
error = correct value- wrong value;
error % is = (error/correct value)*100;
First find error.
error = correct value- wrong value;
error % is = (error/correct value)*100;
Sunil said:
1 decade ago
Why we finally multiplying with 3/5x?
Lorance Mathew said:
1 decade ago
There is a rule.
(Numerator of 1st Fraction X Denominator of 2nd Fraction - Numerator of 2nd Fraction X Denominator of 1st Fraction)/(Denominator of 1st Fraction X Denominator of 2nd Fraction).
= (5 X 5 - 3 X 3)/(5 X 3) = (25 - 9)/15 .
= 16/15.
(Numerator of 1st Fraction X Denominator of 2nd Fraction - Numerator of 2nd Fraction X Denominator of 1st Fraction)/(Denominator of 1st Fraction X Denominator of 2nd Fraction).
= (5 X 5 - 3 X 3)/(5 X 3) = (25 - 9)/15 .
= 16/15.
Chris IT said:
1 decade ago
Take L.C.M for the two numbers and subtract them.
Swetha said:
1 decade ago
Do anyone please tell me how 16/15 came in the simplification of (5/3) - (3/5).
(5/3) - (3/5) = 16/5 how?
(5/3) - (3/5) = 16/5 how?
Vijayakumar said:
1 decade ago
Error% = (true value-false value)*100/true value.
% of error = ((5/3)-(3/5))*100/(5/3).
= (16/15)*100*(3/5).
= 64%.
% of error = ((5/3)-(3/5))*100/(5/3).
= (16/15)*100*(3/5).
= 64%.
Gowtham said:
1 decade ago
30 is the common multiplying factor for the the both 5 and 3.
Then,
30*3/5=18,
30*5/3=50,
Make the answer for 100%
Then 18 became 36 and 50 to 100,
Subtract the final output to get an answer 64%.
Then,
30*3/5=18,
30*5/3=50,
Make the answer for 100%
Then 18 became 36 and 50 to 100,
Subtract the final output to get an answer 64%.
Yugank Garg said:
1 decade ago
(3X/5) *100/ (5x/3) = 36%.
It means 3X/5 is 36% of original 100%.
Therefore percentage error is 64%.
It means 3X/5 is 36% of original 100%.
Therefore percentage error is 64%.
Prasad said:
1 decade ago
Well you took 9 and 25 ok
the difference between 25 and 9 becomes error i.e.. 16
error percentage is error/true value * 100
now 16/25*100 = 64%
the difference between 25 and 9 becomes error i.e.. 16
error percentage is error/true value * 100
now 16/25*100 = 64%
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