c) What is the approximate probability that the mean score of these students Is 21 or higher? Answers: (a) P(X ≥ 21) = P[Z ≥ (21.0-18.6)/5.9] = P(Z ≥ 0.4068) = 1 – 0.6591 = 0.3409 OR 34%.

What is the probability that the mean score of these students is 21 or higher?

c) What is the approximate probability that the mean score of these students Is 21 or higher? Answers: (a) P(X ≥ 21) = P[Z ≥ (21.0-18.6)/5.9] = P(Z ≥ 0.4068) = 1 – 0.6591 = 0.3409 OR 34%.

What is the percentage probability that a student will score more than 80?

To find the probability of scoring more than 80: 0.5 –0.4772 = 0.0228 or 2.28% as a %.

What is the probability that a learner will score less than 60 marks?

If you look at the Z-table for a normal distribution, the P(00.67) = 1–0.49714 = 0.50286. This represents the probability that the student scores <=60 OR >=64. Since we are interested only in students scoring <=60, that probability would be 0.50286/2 = 0.25143.

How do you find probability in statistics?

Divide the number of events by the number of possible outcomes.

  1. Determine a single event with a single outcome.
  2. Identify the total number of outcomes that can occur.
  3. Divide the number of events by the number of possible outcomes.

How do you calculate probabilities?

Divide the number of events by the number of possible outcomes. This will give us the probability of a single event occurring.

What is the 10% condition?

The 10% condition states that sample sizes should be no more than 10% of the population. Whenever samples are involved in statistics, check the condition to ensure you have sound results.

What is probabilities in statistics?

Probability is simply how likely something is to happen. Whenever we’re unsure about the outcome of an event, we can talk about the probabilities of certain outcomes—how likely they are. The analysis of events governed by probability is called statistics.

What is the probability that a given student will score less than 84?

The probability that a given student scores less than 84 is approximately 59.87%. The height of a certain species of penguin is normally distributed with a mean of μ = 30 inches and a standard deviation of σ = 4 inches. If we randomly select a penguin, what is the probability that it is greater than 28 inches tall?

What is the use of Student t test in statistics?

Student T Test is very useful when you have two large samples and their difference between mean is very small. As it uses sample variance, you can compare them to find the best sample. You can think it as an Upgrade of the Z Score.

What is the difference between student’s t distribution and Z test?

In the Student’s T distribution you select various small samples when you don’t know the population standard deviation. You use T – Table to determine the significant difference between the two sets of the data. In Z test you consider only the mean for finding the score but in the t-test, you consider sample variance.

How do you find the probability of a normal distribution?

We can use the following process to find the probability that a normally distributed random variable X takes on a certain value, given a mean and standard deviation: Step 1: Find the z-score. A z-score tells you how many standard deviations away an individual data value falls from the mean.