Answer:
3.67% probability that the mean daily production exceeds 50 pounds.
Step-by-step explanation:
To solve this problem, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a random variable X, with mean
and standard deviation
, a large sample size can be approximated to a normal distribution with mean
and standard deviation 
In this problem, we have that:

For this herd of 80 cattle, what is the probability that the mean daily production exceeds 50 pounds?
This probability is 1 subtracted by the value of Z when X = 50. So

By the Central Limit Theorem



has a pvalue of 0.9633
1 - 0.9633 = 0.0367
3.67% probability that the mean daily production exceeds 50 pounds.