he lifespan (L) of each of 2000 valves is measured and given Calculate the probability that the lifespan of a valve is more than 800 hours Lifespan (hours) Number L>= 1000 800L < 1000 600 L < 800 400L < 600 L < 400 O a. O b. 0.3195 O C. O d. 0.9438 0.5805 0.215 119 520 931 230 200

Let x be a random variable that represents white blood cell count per cubic milliliter of whole blood. Assume that x has a distribution that is approximately normal with a mean u= 7500 and a = 1750. A test result of x < 3500 is an indication of leucopenia. This indicates bone marrow depression that may result in a viral infection. a. What is the probability that on a single test x is less than 3500? b. A patient is given 3 tests at regular intervals. What is the probability that the average of the three tests is less than 3500?

The probability distribution of X, the number of imperfections for every 10 meters of a synthetic fabric in continuous rolls of uniform width, is given by 1 2 3 4 f(x) 0.41 0.37 0.17 0.05 0.01 find the mean and variance of X. (10 pts)

Suppose the lengths of human pregnancies are normally distributed with u = 266 days and 0 = 16 days. The area to the left of X = 245 is 0.0947. What is the probability that a randomly selected human pregnancy lasts

The distribution of the time until a Web site changes is important to Web crawlers that search engines use to maintain current information about Web sites. The distribution of the time until change (in days) of a Web site is approximated in the following table. Days until Probability Changes 1.5 0.05 0.25 0.35 0.20 0.15 3 4.5 7 Calculate the probability mass function of the days until change. *Answers should be in rational numbers with 2 decimal places.

Let the random variable x have a normal distribution with a mean value of 70 and a varience of 25. Then find the probability that P (x<80)

Buy balls online, use normal approximation to estimate the probability of getting exactly 52 bule balls in 100 balls. Assume that bule and red balls are equally likely.

Today, the waves are crashing onto the beach every 4.4 seconds. The times from when a person arrives at the shoreline until a crashing wave is observed follows a Uniform distribution from 0 to 4.4 seconds. Round to 4 decimal places where possible.   The probability that the wave will crash onto the beach between 1.2 and 2.1 seconds after the person arrives is P(1.2 < x < 2.1) =  The probability that it will take longer than 3.28 seconds for the wave to crash onto the beach after the person arrives is P(x > 3.28) =  Suppose that the person has already been standing at the shoreline for 0.7 seconds without a wave crashing in. Find the probability that it will take between 3 and 3.7 seconds for the wave to crash onto the shoreline.  62% of the time a person will wait at least how long before the wave crashes in?  seconds. Find the minimum for the upper quartile.  seconds. Hint:

Find the probability that the city uses more than 45,000 kWh. Please refer to attached image and thank you

The time intervals between successive barges passing a certain point on a busy waterway have an exponential distribution with mean 10 minutes. (a) Find the probability that the time interval between two successive barges is more than 15 minutes. (b) Find a time interval t such that we can be 75% sure that the time interval between two successive barges will be greater than t. Show word count Next