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 2 of 14.
Rohan said:
2 years ago
Just take lcm of 5 and 3 which will be 15.
Now,
3/5 * 15 = 9 and 5/3 * 15 = 25.
Now subtract 25 by 9 25 - 9 = 16.
Now 16/25 * 100 = 64%.
Now,
3/5 * 15 = 9 and 5/3 * 15 = 25.
Now subtract 25 by 9 25 - 9 = 16.
Now 16/25 * 100 = 64%.
(43)
AASHIKA said:
2 years ago
@All
Firstly,
Take a base number and multiply it;
5x3 = 15.
Then,
15 x 3/5 =9,
15 x 5/3 =25,
Difference 25-9 = 16.
16/25 x 100 = 64%.
Thanks.
Firstly,
Take a base number and multiply it;
5x3 = 15.
Then,
15 x 3/5 =9,
15 x 5/3 =25,
Difference 25-9 = 16.
16/25 x 100 = 64%.
Thanks.
(82)
Madangopal Laturkar said:
3 years ago
Take base number and multiply it;
5 * 3 = 15.
Then,
15 * 3/5 = 9,
15 * 573 = 25,
Difference 25 - 9 = 16.
16/25 * 100 = 64%.
5 * 3 = 15.
Then,
15 * 3/5 = 9,
15 * 573 = 25,
Difference 25 - 9 = 16.
16/25 * 100 = 64%.
(49)
Raj said:
3 years ago
How 16/15 came? Please explain.
(9)
M.Lokesh said:
3 years ago
Error comes from true value so;.
Error% = error/true value.
Error% = error/true value.
(18)
Tufayel BD said:
3 years ago
Let number is 100.
Actual Multiplication = (100 *5)/3 = 500/3.
Student multiplied = (100 *3)/5 = 300/5.
Error,
= (500/3) - (300/5),
= (2500 - 900)/15,
= 1600/15.
%Error = (1600 *100 *3)/(15*500) = 64%.
Actual Multiplication = (100 *5)/3 = 500/3.
Student multiplied = (100 *3)/5 = 300/5.
Error,
= (500/3) - (300/5),
= (2500 - 900)/15,
= 1600/15.
%Error = (1600 *100 *3)/(15*500) = 64%.
(17)
Helal said:
3 years ago
Let, X be the exact value.
And Y be the error value.
Now, the formula for percentage error= (X-Y)/X *100%
{(5/3-3/5)÷5/3}*100%.
= (16/15*3/5)*100%,
= 64%.
And Y be the error value.
Now, the formula for percentage error= (X-Y)/X *100%
{(5/3-3/5)÷5/3}*100%.
= (16/15*3/5)*100%,
= 64%.
(11)
Venkatesh said:
4 years ago
Thank you @Srihari.
(3)
Pooja said:
4 years ago
@Pradip Zala: at last, why we take 100/500. Can you explain?
Guru said:
4 years ago
Lets take the number is 15.
Correct value is 5/3*15 = 25.
The error value is 3/5 * 15 = 9,
The difference is 11,
So 11/25*10 = 64.
Correct value is 5/3*15 = 25.
The error value is 3/5 * 15 = 9,
The difference is 11,
So 11/25*10 = 64.
(6)
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