Question

Two students performed the same experiment separately and each one of them recorded two readings of mass which are given below. Correct reading of mass is 3.0 g. On the basis of given data, mark the correct option out of the following statements.

Student	Reading (i)	Reading (ii)
A	3.01	2.99
B	3.05	2.95

• A. Results of student B are both precise and accurate
• B. Results of student A are both precise and accurate.
• C. Results of student B are neither precise nor accurate.
• D. Results of both the students are neither accurate nor precise.

Answer 1

The correct option is D Results of both the students are neither accurate nor precise.

Analysing the data

Correct reading of mass = 3.0 g

Individual reading recorded by both students are as follows:

Student	Reading (i)	Reading (ii)
A	3.01	2.99
B	3.05	2.95

Using appropriate formula and concepts to solve the given question

Average of reading =

$\frac{\text{reading 1 + reading 2}}{\text{Total no of readings taken}}$

Average of readings of student A:

A = $\frac{3.01+2.99}{2}=3$

Average of readings of student B:

B = $\frac{3.05+2.95}{2}=3$

Checking for accuracy:

• For both students, average value is close to the correct reading, which implies that readings of both students A and B are accurate.

Checking for precision:

• Readings taken by student A is very close to 3.00 and the difference between those readings is 0.02 thus readings of Student A are precise.
• Readings taken by student B are not that close to 3.00 and the difference between those readings is 0.10 thus readings of Student B are not precise.

The readings taken by student A are both accurate and precise. Hence, correct answer is option A.