Suppose that the average amount of time a student studies for an exam follows a normal distribution with a mean of 6 hours with a standard deviation of 3.15 hours. What is the probability that a student studies less than 10 hours?
A.
0.1020
B.
0.7525
C.
-1.27
D.
0.8980
Suppose that the average amount of time a student studies for an exam follows a normal...
The average time taken to complete an exam, X, follows a normal probability distribution with mean = 60 minutes and standard deviation 30 minutes. What is the probability that a randomly chosen student will take more than 45 minutes to complete the exam?
IV. Continuous Distribution: Normal Normal 1. The average time to complete a final exam in a given course is normally distributed. With average of 80 min, and standard deviation of 8 minutes. For a certain student taken at random: to. What is the probability of finishing the exam in an hour or less? b. What is the probability of finishing the exam between 60 min and 70 min? Exponential 2. The time to fail in hours of a laser beam...
Suppose the amount of time college students sleep per night follows a normal distribution with mean 8 hours and standard deviation 0.75 hours. Let Y denote the amount of time a randomly selected student sleeps per night. What is P(7 < Y <9)? Round to 4 decimal places.
Suppose the distribution of Y = the amount of time it takes for a randomly selected student to complete a particular exam is normal with mean 43.7 minutes and standard deviation 4.6 minutes. Suppose those students who go past a 50 minute time limit are tortured by Dr. Robinson’s singing until they complete the exam. a. Show that the probability of a randomly selected student avoiding any torture is .91459. (6 decimals) b. If 10 students take the exam, what...
5. Suppose that the time (in hours) that Isabel spends on an untimed final exam exponential distribution with mean 1.25 hours, and the time that Javier spends follows an exponential distribution with mean 1.75 hours. Assume independent of each other. (a) Determine the probability that Isabel finishes in less than 1 hour ollows an on the same exam that their times are (b) Determine the probability that Javier finishes in less than 1 hour.
5. Suppose that the time (in...
let x be the random variable that represent the lenght of time it takes a student to complete maths 23 exam. it was found that x has an approximately normal distribution with mean 1.5 hours and standard deviation =025 hours. (a) what is the probability that it takes at least 1.4 hours for a randomly selected student to complete the exam? (b) suppose 25 students are selected at random,what is the probability that the mean time x of completing the...
The Office of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 20 hours. The hours studied follows the normal distribution with a population standard deviation of six hours. Suppose we select a random sample of 144 current students. What is the probability that the mean of this sample is less than 19.25 hours? Group of...
let x be a random variable that represents the length of time it takes a student to complete a MTH 23 exam.It was found that x has an approximately normal distribution with mean =1.5 hours and standard deviation =.25 hours. (a) What is the probability that it takes at least 1.4 hours for a randomly selected student to complete the exam? (b) Suppose 25 student are selected at random. What is the probability that the means time of completing the...
Reaction time studies are studies in which participants receive a stimulus and the amount of time it takes for them to react is measured. In one simple type of reaction time study, each participant holds a clicker button and stares at a screen. When the participant sees a part of the screen light up, he or she clicks the button as quickly as possible. The researcher then records how much time elapsed between when the screen lit up and when...
11. A Biology instructor is wondering about the average amount of time a student spent studying for a test. She asks a random sample of 18 of her students for their amount of study time and determines that the mean study time in the sample is 6.3 hours with a standard deviation in the sample of 1.94 hours. She believes that it is reasonable to assume that the overall distribution of study times is normal. Give this instructor a 98%...