Search results
Nov 5, 2020 · The z score tells you how many standard deviations away 1380 is from the mean. Step 1: Subtract the mean from the x value. x = 1380. M = 1150. x – M = 1380 − 1150 = 230. Step 2: Divide the difference by the standard deviation. SD = 150. z = 230 ÷ 150 = 1.53. The z score for a value of 1380 is 1.53.
Apr 2, 2023 · x = μ + (z)(σ) = 5 + (3)(2) = 11. The z -score is three. Since the mean for the standard normal distribution is zero and the standard deviation is one, then the transformation in Equation 6.2.1 produces the distribution Z ∼ N(0, 1). The value x comes from a normal distribution with mean μ and standard deviation σ.
- Suppose X ~ N(5, 6). This says that X is a normally distributed random variable with mean μ = 5 and standard deviation σ = 6. Suppose x = 17.
- Some doctors believe that a person can lose five pounds, on the average, in a month by reducing their fat intake and by exercising consistently.
- The mean height of 15 to 18-year-old males from Chile from 2009 to 2010 was 170 cm with a standard deviation of 6.28 cm. Male heights are known to follow a normal distribution.
- Problem. From 1984 to 1985, the mean height of 15 to 18-year-old males from Chile was 172.36 cm, and the standard deviation was 6.34 cm. Let Y = the height of 15 to 18-year-old males from 1984 to 1985.
3 days ago · The normal distribution, which is continuous, is the most important of all the probability distributions. Its graph is bell-shaped. This bell-shaped curve is used in almost all disciplines. Since it is a continuous distribution, the total area under the curve is one. The parameters of the normal are the mean \(\mu\) and the standard deviation σ.
Jan 21, 2021 · Definition 6.3.1 6.3. 1: z-score. z = x − μ σ (6.3.1) (6.3.1) z = x − μ σ. where μ μ = mean of the population of the x value and σ σ = standard deviation for the population of the x value. The z-score is normally distributed, with a mean of 0 and a standard deviation of 1. It is known as the standard normal curve.
This z-score tells you that x = 10 is 2.5 standard deviations to the right of the mean five. z= –4. This z-score tells you that x = –3 is 4 standard deviations to the left of the mean. Suppose the random variables X and Y have the following normal distributions: X ~ N(5, 6) and Y ~ N(2, 1). If x = 17, then z = 2. (This was previously shown.)
People also ask
What is the z-score of a normal distribution?
How many x values are within a standard deviation of the mean?
What is the mean and standard deviation of a normal distribution?
How do you indicate a standard normal distribution?
How far below the mean is x = 1?
What if (x) equals the mean?
Suppose x has a normal distribution with mean 50 and standard deviation 6. About 68 percent of the x values lie within one standard deviation of the mean. Therefore, about 68 percent of the x values lie between –1σ = (–1)(6) = –6 and 1σ = (1)(6) = 6 of the mean 50. The values 50 – 6 = 44 and 50 + 6 = 56 are within one standard ...