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?

34%
44%
54%
64%
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 5 of 14.

Linoj said:   6 years ago
Thank you @Ameer.

Sanghavi said:   6 years ago
I am not getting it. Please explain me.

Aditya said:   6 years ago
We can take 100 as a number then multiply 3/5 and 5/3 as well. U will get 60 and 166.5, then
166.5-60 = 106.5.

(106.5/166.5) * 100 = 64%.

Harish said:   6 years ago
Assume the number to be multiplied as 30.
The actual value is (5/3*30) =50.
But his value is (3/5*30) =18.
So the error is 32.
Here, 50 is 100% then 32 is 64%.
Therefore error is 64%.

P DHAMODARASAMY said:   6 years ago
Problem is 3/5 instead of 5/3.

So, we treat is as a ratio which is 3/5: 5/3,
Take lcm for 5 and 3, is 15,
Hence 3 * 15/5 : 5*15/3.
9:25. so the difference is 16.
Finally, 16 %of 25 is 64%.

Geet said:   6 years ago
Will it be 60/166*100?

Deepak Kumar MR said:   6 years ago
(3/5)/(5/3) = 9/25 so in fractions it is 0.36 minus this value with 1-0.36 = 0.64 which is 64%.

Ameer said:   6 years ago
Let's say the number is = 100.
3/5 * 100 = 60 and 5/3 * 100 = 166.66,
Error = 166.66-60 = 106.66.
Error% = error/true value.
=106.66/(5/3),
= 64( for percetage i.e 64%).

Sandeep said:   7 years ago
We have multiplied a number by 3/5 instead of 5/3.
So, just find the difference between them,
5/3 - 3/5 = 16/15,
Now let's find out the error %,
For that, we have to take "the difference value" & "the multiplied value",
(16/15 * 3/5 * 100) = 64.

S.AMIN ULLAH said:   7 years ago
How 16x/15 has been solved?

Please, Anybody can explain me this?


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