A candidate was to subtract 15 from a certain number but mistakenly added 25 and his answer was 145 find the percentage error
To find the percentage error, we need to calculate the difference between the correct answer and the candidate's answer, and then express that difference as a percentage of the correct answer.
Let's break down the steps:
1. The candidate was supposed to subtract 15 from a certain number, but instead, they added 25. So, we can consider the candidate's answer as the result of adding 25 to the correct number.
Let's denote the correct number as "x."
The candidate's answer = x + 25
2. The candidate's answer was 145. So we have the equation:
x + 25 = 145
We can solve this equation to find the correct value of "x."
Subtracting 25 from both sides:
x = 145 - 25
x = 120
Now we know that the correct number is 120.
3. To find the percentage error, we calculate the difference between the candidate's answer (145) and the correct answer (120), and then express that difference as a percentage of the correct answer.
Difference = Candidate's answer - Correct answer
Difference = 145 - 120
Difference = 25
Now, we calculate the percentage error:
Percentage Error = (Difference / Correct answer) x 100
Percentage Error = (25 / 120) x 100
Percentage Error ≈ 20.83%
So, the percentage error in this case is approximately 20.83%.