6. Suppose Steve goes fishing near the nuclear power plant at Hawkins. He’s interested in catching King Salmons and Walleyes. Assume the following: • All species of fish in the lake have weights that are normally distributed. • The weight of the King Salmons are i. i.d. ∼ Normal with µK = 150 lbs and σK = 10 lbs. Let K be the weight of a randomly caught King Salmon. • The weight of the Walleyes are i. i.d. ∼ Normal with µW = 51 lbs and σW = 9 lbs. Let W be the weight of a randomly caught Walleye. (a) (3 points) Suppose Steve catches 4 King Salmons at random. What is the probability that the total weight of the King Salmons caught is greater than 575 lbs?

89.44% probability that the total weight of the King Salmons caught is greater than 575 lbs

Step-by-step explanation:

To solve this question, 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 normally distributed random variable X, with mean and standard deviation , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean and standard deviation .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

For sums of size n from a population, the mean is and the standard deviation is

The weight of the King Salmons are i.i.d. ∼ Normal with µK = 150 lbs and σK = 10 lbs. 4 king salmons.

So

What is the probability that the total weight of the King Salmons caught is greater than 575 lbs?

This is 1 subtracted by the pvalue of Z when X = 575. So

has a pvalue of 0.1056

1 - 0.1056 = 0.8944

89.44% probability that the total weight of the King Salmons caught is greater than 575 lbs

3/4 ÷ 3/4

step-by-step explanation:

basically divide any proper fraction with itself to fit the criteria.

so if we are using 3/4, then:

3/4 ÷ 3/4 = 1

so 1 is the quotient.

and the numerators for both these fractions is 3.   and if we divide the numerators:

3 ÷ 3 = 1

we see that quotient is equal to our original quotient as well.

99

step-by-step explanation: