Probability problem

Our psychology department received a new statistics text for review. Prof. Smart in his review provided an interesting table of corrections. TYPE: Alterations-20%, Spelling-50%, Spelling and alterations-10% Assuming that spelling and alterations are the only possible types of corrections, calculate. (Please help!) The probablility of spotting a correction due to an alteration error or a spelling error. AND the probability of detecting no correction. I have tried this question and am having trouble. I have requested help from Brainmass and I am more confused by the response. Particularily why I am subtracting 10% from the 20%(Spelling) and 50% (Alterations). Please clarify. My Answ... click for more

Probability questions- Independent events

Jill wants to do her MBA in Statistics at a B.C. university. She applies to two universities that offer post-graduate degrees in Statistics. Assume that the acceptance rate at University A is 25% and at University B is 35%. Further assume that acceptance at the two universities are independant events. A) What is the probability that Jill will be accepted by both universities? B) What is the probability that neither university will accept Jane? C) What is the probability that Jill will be accepted by at least one of the two universities? D) What is the probability that one and only one will accept Jill?

Probability Calculations- Probability distribution, Expected value

Harvard University published the age profile of it's first time students. A random sample of 33 students has ten students in their thirties, fifteen students in their forties, five students in their fifties, and three students in their sixties. A student is selected randomly from the sample. Let X be the age of the selected student. Calculate the: A) Probability that the student is of age 30 B) Probability that the student is of age 50 or 60 C) Probability distribution of X D) Expected value of X

Normal (z) Distributions- In grading Oranges into "A","B" and "C", a large orchard uses weights to distinguish Oranges. If the day's pick shows 16.6% are grade "A" and 6.68% are grade "C", determine the Mean and Standard Deviation.

In grading Oranges into "A","B" and "C", a large orchard uses weights to distinguish Oranges. Any Orange weighing more than 2 ounces is classified as grade "A", while an Orange weighing less than 0.75 ounces is classified as grade "C". If the day's pick shows 16.6% are grade "A" and 6.68% are grade "C", determine the Mean and Standard Deviation. Assume the weights are normally distributed. Hint: First calculate the appropriate z values for the probabilities given,then set up the equations to solve for the Mean and the Standard Deviation.

Binomial Probability Distribution

The manager of the local Tim Horton's found that 60% of her employees call in sick on Fridays before the long weekend. Out of a sample of ten employees, what is the probability that: A) exactly three employees will call in sick B) not more than one employee will call in sick. C) at least three employees will show up for work on Fridays before the long weekend.