Question

The standard deviation of marks scored by PUC students in an examination is 10.5. The mean marks scored by 64 students of a college is 38. Can we conclude at 1% level of significance that mean marks of PUC students is 40?

Answer 1

Given: σ=10.5, n = 64 

x̄=38, p = 40, µ= 1%

H₀ = Mean marks of PUC students is 40. 

( i.e., H₀ = : µ = 40)

H₁ = Mean marks of PUC students differs from 40.

( i.e,. H₁ = : µ ≠ 40)

At α = 1% the two tail critical values are -K₁ 

= 2.58 and + K₂ 

= + 2.58

Here, Zeal = -1.52 is in between -K₁ and K₂. 

H₀ is accepted. 

Conclusion : Mean marks of PUC students is 40.