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## Matthew S.'s Resources

If you'll be using a textbook for class, perhaps you can buy it in advance, or gain access to the online textbook so you can begin getting familiar with the concepts in algebra.  That might help lessen your anxiety.  Plus remember you're going into the class to learn; no one expects...

You need to convert this problem to a standard normal distribution to calculate the probability.  That means you convert the systolic number 120 to a Z-score.  Z = ( X - μ ) / σ, and you know all three variables. Z = (120 - 120)/8 = 0/8 = 0. P(X > 120) = P(Z > 0) = 0.5000,...

You could do it either way, but I'd learn towards n=48 for all questions since you are repeatedly referring to the 'fast track group'.  There should certainly be an expectation that not all candidates' data can be used; in the 'real world' you'll be tossing data if it is unusable.

The formula for the volume of a sphere is given by V = (4/3)πr3 Since the radius is 7 cm, let's substitute that in: V = (4/3)(3.14)(7 cm)3 V = 1436.755 cm3 = 1437 cm3, rounding to the nearest whole unit as requested. Is that the answer you got?

53030000. is the number in question.  For every position you move the decimal point left, that is a power of 10.  If you move it until the first digit is the only thing left of the decimal point, you will have shifted the decimal place left 7 positions. 53030000 is the same was 5.303...

Let's use A to represent the number of adult tickets sold, and C for the number of children's tickets sold. We know the cost of each ticket, and the total amount of sales. We also know how many tickets were sold. Let's write the known information in equation form. A + C = 460 <-- Total number...

Two lines are parallel to one another if their equations have the same slope.  y=2x-8 has a slope of 2, so we can use that fact plus the given point (3,-1) to solve the problem. Using the equation (y - y1) = m (x - x1), let's add in m, and our point (x1, y1): y - (-1) = 2 ( x -...

n! refers to a factorial, a product of n numbers, each one less than the preceding value. You can write a factorial n! by starting with the number n, multiplying it by one less than the previous number, and repeat until you reach 1, at which time you can stop. So 5! can be written as follows:...

Your cylinder formula looks more like the formula for a circle, since there's no mention of a height, z.  You can get to the radius from the generic equation x2+y2=r2; the radius of the circle would appear to be 2.  As for the height, I'm not sure if it matters.  If you assumed...

Is the quantity to the right of the equals sign (8/x) + 1 or 8/(x+1)?  Unfortunately there's no easy way to write out fractions here, so the next best thing is to use parentheses and/or brackets to make it clear what's in the numerator and what's in the denominator.  That helps...

This is an example of a binomial event and probability distribution.  For each person you select, they are either overweight or not-only two possible outcomes.  If we define 'success' as selecting an overweight person, the probability of success when we select someone is denoted p,...

Suppose you had a bag of 8 marbles, 3 red and 5 blue.  What is the probability of choosing a red marble on the 3rd draw? If the first two marbles are not replaced after being drawn, then the 3rd draw is an example of a dependent event, because, obviously, there won't be 8 marbles in the...

The benefit to stem and leaf is that, unlike a histogram, you actually get to see every value in your data set, whereas histograms are based on the counts of data points within certain ranges of numbers that define the bins used to construct the histogram.  Sorting the leaves in ascending...

The key here is remembering that a given normal distribution's mean and standard deviation, if not 0 and 1, respectively, requires converting the x values into Z values, to be able to use a Z table to look up the correct probabilities. You also have to determine if the value you looked up matches...

Let's use the method you listed above, but we need to correct the formula: (and note "T+a") is not the a that is in the first term, it is an angle, which I will represent with delta, δ): a cos θ + b sin θ = c cos ( θ - δ ) The original equation, if we switch the order...

We have to convert the x-values to z-values first, and then look up areas to the left of the z-values on a standard normal distribution table, and, once we have those areas, determine if they represent the area under the curve we need. μ = 55, σ = 7 for our normal distribution; that is given...

For this problem, you will be using the Z-table to look up probabilities. We know the standard normal distribution has a mean of 0 and standard deviation of 1, but the normal distribution of times given in this problem does not match that for the standard normal (since mean = 36 and sd = 2.5)...

The total area under the standardized normal distribution curve is 1.  If you have a textbook handy, there should be "Z-tables" in it that list areas under the curve to the LEFT of the Z-value.  For Z=0, the area to the left of the curve is 0.5000, since the curve is symmetric...

It is certainly possible to have multiple outliers.  How big is your data set?