Using z-scores, it is found that the value of z is z = 1.96.
-----------------------------
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula, which for a measure X, in a distribution with mean 
and standard deviation 
, is given by:
- It measures how many standard deviations the measure is from the mean.
- Each z-score has an associated p-value, which is the percentile.
- The normal distribution is symmetric, which means that the middle 95% is between the <u>2.5th percentile and the 97.5th percentile</u>.
- The 2.5th percentile is Z with a p-value of 0.025, thus Z = -1.96.
- The 97.5th percentile is Z with a p-value of 0.975, thus Z = 1.96.
- Thus, the value of Z is 1.96.
A similar problem is given at brainly.com/question/16965597
9514 1404 393
Answer:
- $304
- $91.83
Step-by-step explanation:
1. The finance charge is found from the simple interest formula;
I = Prt
where P is the principal amount, r is the annual rate, and t is the number of years.
24 months is 2 years, so the interest charged is ...
I = $1900×0.08×2 = $304
The finance charge is $304.
__
2. The monthly payment will be the total amount due, divided by the number of months.
payment = ($1900 +304)/24 = $2204/24 ≈ $91.83
The monthly payment is $91.83.
Answer:
Step-by-step explanation:
Hello!
The variable of interest is:
X: number of daily text messages a high school girl sends.
This variable has a population standard deviation of 20 text messages.
A sample of 50 high school girls is taken.
The is no information about the variable distribution, but since the sample is large enough, n ≥ 30, you can apply the Central Limit Theorem and approximate the distribution of the sample mean to normal:
X[bar]≈N(μ;δ²/n)
This way you can use an approximation of the standard normal to calculate the asked probabilities of the sample mean of daily text messages of high school girls:
Z=(X[bar]-μ)/(δ/√n)≈ N(0;1)
a.
P(X[bar]<95) = P(Z<(95-100)/(20/√50))= P(Z<-1.77)= 0.03836
b.
P(95≤X[bar]≤105)= P(X[bar]≤105)-P(X[bar]≤95)
P(Z≤(105-100)/(20/√50))-P(Z≤(95-100)/(20/√50))= P(Z≤1.77)-P(Z≤-1.77)= 0.96164-0.03836= 0.92328
I hope you have a SUPER day!
Answer:
-142
Step-by-step explanation:
First solve parenthesis,
(12) - (23 +131) =
(12) -154
Finally subtract,
12-154
= -142
