A student measured the length of a room as 4.00\text{ m} instead of the actual length of 5… — JAMB UTME

A student measured the length of a room as $4.00\text{ m}$ instead of the actual length of $5.00\text{ m}$ . What is the percentage error in the measurement?

$20\%$ Answer
B
$25\%$
C
$80\%$
D
$2\%$

Answer

20\%

The absolute error is the difference between the measured value (

4.00\text{ m}

) and the actual value (

5.00\text{ m}

), which is

1.00\text{ m}

. Dividing the error by the actual value gives $\frac{1.00}{5.00} = 0.20$, which equals

20\%

when expressed as a percentage.

Step-by-Step Solution

Identify the actual value and the measured value.

Actual length =

5.00\text{ m}

, Measured length =

4.00\text{ m}

Percentage error calculations require establishing the true baseline quantity.

Calculate the absolute error.

Absolute Error =

|5.00 - 4.00| = 1.00\text{ m}

Error is defined as the magnitude of the difference between the true value and measured value.

Compute the percentage error.

Percentage Error = $\frac{1.00}{5.00} \times 100\% = 20\%$.

Percentage error is found by dividing the absolute error by the actual value and multiplying by

100\%

Key Concept

Percentage Error Calculation

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic