The probability of the sample is 0.5 or 50%
Explanation:
Given:
Mean, μ = 20
Standard deviation, δ = 1.3
Probability of sample being less than 20.1 = ?
P (x < 20.1) = 20.1 - μ / δ √n
P (x < 20.1) = [tex]\frac{20.1 - 20}{1.3\sqrt{61} }[/tex]
= 0.0098
P( x < 20.1) = P(z < 0.0098)
P (z < 0.0098) = 0.5
The value of P is found out using a z score table.
Therefore, probability of the sample is 0.5 or 50%