Test Index

NCERT Class XI Mathematics - Statistics - Solutions

© examsnet.com
Question : 33
Total: 34
The mean and standard deviation of marks obtained by 50 students of a class in three subjects, Mathematics, Physics and Chemistry are given below :
Subject MathematicsPhysics Chemistry
Mean42 32 40.9
Standard deviation12 15 20

Which of the three subjects shows the highest variability in marks and which shows the lowest?
Solution:  
For Mathematics,
−
x
 = 42 and σ = 12
∴ C.V. of Mathematics =
12
42
 × 100 = 28.57
For Physics,
−
x
 = 32 and σ = 15
∴ C.V. of Physics =
15
32
 × 100 = 46.88
For Chemistry,
−
x
 = 40.9 and σ = 20
∴ C.V. of Chemistry =
20
40.9
 × 100 = 48.9
Thus Chemistry with highest C.V. shows the highest variability and Mathematics with lowest C.V. shows the lowest variability.
© examsnet.com
Go to Question:
Prev Question
Next Question