It is a striking fact that the first digits of numbers in legitimate records often follow a distribution known as Benford's Law, shown below. First digit 1 2 3 4 5 6 7 8 9 Proportion 0.289...

It is a striking fact that the first digits of numbers in legitimate records often follow a distribution known as Benford's Law, shown below. First digit 1 2 3 4 5 6 7 8 9 Proportion 0.289...

The College Board finds that the distribution of students' SAT scores depends on the level of education their parents have. Children of parents who did not finish high school have SAT math scores...

a corporation calculates that the cost of photcopies follows a normal distrubution with a mean of 500$ per month and a standard deviation of $50 per month.

A state has a lottery game where a person picks one of the 1000? three-digit numbers between 000 and 999. The lottery selects a? three-digit number at random. With a bet of? $1, a person wins $500...

The test scores on the quantitative portion of the Scholastic Aptitude Test (SAT) are normally distributed with a mean score of 570 and SD of 70. Using the empirical rule, approximately what percent...

An educational psychologist wishes to know the mean number of words a third grader can read per minute. She wants to make an estimate at the 80% level of confidence. For a sample of 448 third graders,...

What units would you expect to see if you were calculating the sample STANDARD DEVIATION of sales from a convenient store?

he amount of money that a student at harvard university carries on his/her person is normally distributed with a mean of $25 and a standard deviation of $5. What is the probability that a randomly...

A lot consists of 15 articles of which 8 are free of defects ,4 have minor defects and 3 have major defects.Five articles are selected at random without replacement find probability that at most one...

A nonnegative integer-valued random variable X has a CDF of the form F(x)=1-(1/5)^x for x=1,2,.....and zero otherwise. Find P(X is odd)? could you please help me with that?

A bank manager decides to study waiting times of customers for teller service at the noon lunch hour (noon to 1pm). He selects one customer every 20 minutes to measure the time the customer enters...

in a standard normal distribution find the area under the cure for z -scores less than -1.23 round to the 4 decimal places?

Suppose 40% of the restaurants in a certain part of a town are in violation of the health code. A health inspector randomly selects seven of the restaurants for inspection.

Suppose a lie detector test has the following properties.If the suspect is telling the truth,the lie detector will correct say so with probability 0.85.if the suspect is lying ,it will correctly identify...

I'm learning statistics all over again. I need to see how to find the area under the curve using z tables.

A) What is the chance of obtaining a birth weight of 141 oz or heavier when sampling birth records at random? B) What is the chance of obtaining a birth weight of 120 or lighter?

A bus starts with five people and makes 10 stops . assume that passengers are equally likely to get off at any stop. A)describe the sample space and calculate the number of different outcomes...

The amounts of nicotine in a certain brand of cigarette are normally distributed with a mean of 0.933 g and a standard deviation of 0.308 g. Find the probability of randomly selecting a cigarette...

assume that x and y are independent with x ~EXP(2) and Y~Exp(1) Find the probability that the roots of the equation h(t)=0 are real where h(t)=t^2+2tx+y Could you please help...

A computer terminal can pick up an erroneous signal from the keyboard that does not show up on the screen. This creates a silent error that is difficult to detect. Assume that for a particular...

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