Help on 2 pleeeeeaaassseee

If IQ scores are normally distributed with a mean of 100 and a standard deviation of 5, what is the probability that a person se

notsponge [240]

Answer:

2.28% probability that a person selected at random will have an IQ of 110 or higher

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

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.

In this problem, we have that:

$\mu = 100, \sigma = 5$

What is the probability that a person selected at random will have an IQ of 110 or higher?

This is 1 subtracted by the pvalue of Z when X = 110. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{110 - 100}{5}$

$Z = 2$

$Z = 2$ has a pvalue of 0.0228

2.28% probability that a person selected at random will have an IQ of 110 or higher

5 0

2 years ago

The Eco Pulse survey from the marketing communications firm Shelton Group asked individuals to indicate things they do that make

BabaBlast [244]

Answer:

a) 0.54 = 54% probability that a randomly selected person will feel guilty for either wasting food or leaving lights on when not in a room or both.

b) 0.46 = 46% probability that a randomly selected person will not feel guilty for either of these reasons

Step-by-step explanation:

We use Venn's Equations for probabilities.

I am going to say that:

P(A) is the probability that a randomly selected person will feel guilty about wasting food.

P(B) is the probability that a randomly selected person will feel guilty about leaving lights on when not in a room.

0.12 probability that a randomly selected person will feel guilty for both of these reasons.

This means that $P(A \cap B) = 0.12$

0.27 probability that a randomly selected person will feel guilty about leaving lights on when not in a room.

This means that $P(B) = 0.27$

0.39 probability that a randomly selected person will feel guilty about wasting food

This means that $P(A) = 0.39$

a. What is the probability that a randomly selected person will feel guilty for either wasting food or leaving lights on when not in a room or both (to 2 decimals)?

$P(A \cup B) = P(A) + P(B) - P(A \cap B) = 0.39 + 0.27 - 0.12 = 0.54$