Question

The amount of tea leaves in a can from a particular production line is normally distributed with µ = 140 grams and σ = 30 grams. A sample of 26 cans is to be selected.

What is the probability that the sample mean will be greater than 100 grams?

Answer 1

Solution :

Given that ,

mean = = 140

standard deviation = = 30

= / n = 30 / 26 = 5.8835

P( > 100) = 1 - P( < 100)

= 1 - P[( - ) / < (100 - 140) /5.8835 ]

= 1 - P(z < -6.80)

= 1 - 0 = 1.0000

Probability = 1.0000