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 8 of 14.
Madhu said:
8 years ago
Error%={(true value-false value)/true value}*100.
={(5/3-3/5)/5/3}*100,
={16/25}*100,
=64%.
={(5/3-3/5)/5/3}*100,
={16/25}*100,
=64%.
Srilekha said:
8 years ago
If we get error as a negative number them what we have to do?
Sudhan said:
9 years ago
@Srihari.
Your method is awesome, Thank you.
Your method is awesome, Thank you.
Sharmila said:
9 years ago
I understand multiplication errors but what if someone substracted a number instead of adding?Can we still calculate %error? If can't why?
Please explain someone.
Please explain someone.
Ganesh said:
9 years ago
@Sudershan. Thanks for your solution.
MaDX said:
9 years ago
@Raj, We have to find error %.
And like S.P and C.P, the percentage are calculated from the original value.
1.First we have to find the error:
Error = Original value - Wrong value.
= (5/3 x) - (3/5 x).
= 16/15x.
2.Then percentage for error in original.
error% = error/original * 100;
= (16/15 x)/(5/3 x) * 100.
= 64%.
So 64%.
And like S.P and C.P, the percentage are calculated from the original value.
1.First we have to find the error:
Error = Original value - Wrong value.
= (5/3 x) - (3/5 x).
= 16/15x.
2.Then percentage for error in original.
error% = error/original * 100;
= (16/15 x)/(5/3 x) * 100.
= 64%.
So 64%.
Rakesh said:
9 years ago
Great answer @Srihari.
Raj said:
9 years ago
What is the logic behind the term (16x/15 * 3/5x)?
Ybm said:
9 years ago
The shortcut is (Diff ÷ original number)100.
Jac said:
9 years ago
This session is very helpful. Thanks.
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