Modern medical practice tells us not to encourage babies to become too fat. Is there a positive correlation between the weight x of a 1-year-old baby and the weighty of the mature adult (30 years old)? A random sample of medical files produced the following information for 14 females:

$$\scriptstyle\begin{matrix} \text{x (lb)} & \text{21} & \text{25} & \text{23} & \text{24} & \text{20} & \text{15} & \text{25} & \text{21} & \text{17} & \text{24} & \text{26} & \text{22} & \text{18} & \text{19}\\ \text{y (lb)} & \text{125} & \text{125} & \text{120} & \text{125} & \text{130} & \text{120} & \text{145} & \text{130} & \text{130} & \text{130} & \text{130} & \text{140} & \text{110} & \text{115}\\ \end{matrix}$$

$\Sigma x=300$; $\Sigma y=1775$; $\Sigma x^{2}=6572$; $\Sigma y^{2}=226,125$; $\Sigma x y=38,220$ Test the claim that the population correlation coefficient $\boldsymbol{\rho}$ is positive at the 1% level of significance.

In a game of craps, you roll two fair dice. Whether you win or lose depends on the sum of the numbers occurring on the tops of the dice. Let x be the random variable that represents the sum of the numbers on the top of the dice. (a) What values can x take on? (b) What is the probability distribution of these x values (that is, what is the probability that x = 2, 3, etc?)

DNA molecules consist of chemically linked sequences of the bases adenine, guanine, cytosine, and thymine, denoted A, G, C, and T. A sequence of three bases is called a codon. A base may appear more than once in a codon. a. How many different codons are there? b. The bases A and G are purines, while C and T are pyrimidines. How many codons are there whose first and third bases are purines and whose second base is a pyrimidine? c. How many codons consist of three different bases?

Previous studies have shown that urban bus drivers have an extremely stressful job, and a large proportion of drivers retire prematurely with disabilities due to occupational stress. These stresses come from a combination of physical and social sources such as traffic congestion, incessant time pressure, and unruly passengers. In the paper, “Hassles on the Job: A Study of a Job Intervention With Urban Bus Drivers” (Journal of Organizational Behavior, Vol. 20, pp. 199-208), G. Evans et al. examined the effects of an intervention program to improve the conditions of urban bus drivers. Among other variables, the researchers monitored diastolic blood pressure of bus drivers in downtown Stockholm, Sweden. The data, in millimeters of mercury (mm Hg), on the WeissStats CD are based on the blood pressures obtained prior to intervention for the 41 bus drivers in the study. Use the technology of your choice to do the following. a. Obtain a normal probability plot, boxplot, histogram, and stem-and-leaf diagram of the data. b. Based on your results from part (a), can you reasonably apply the one-mean t-test to the data? Explain your reasoning. c. At the 10% significance level, do the data provide sufficient evidence to conclude that the mean diastolic blood pressure of bus drivers in Stockholm exceeds the normal diastolic blood pressure of 80 mm Hg?

The four organs from which fluid output occurs are the _____, _____, _____, and _____.

The outcome of chance events in a fantasy role-playing game is determined by rolling polyhedral dice with anywhere from 4 to 20 sides. Suppose you roll a 16 -sided die 5 times and observe the number on the top of the die. How many possible outcomes are there for these 5 rolls?

Why is surgery an effective treatment for only half of the persons diagnosed with lung cancer?

Indicate which of the following are valid statistical questions. Explain your reasoning. How many people visited Acadia National Park last Tuesday?

To determine whether a sample should be treated as a simple random sample, which is more important: a good knowledge of statistics, or a good knowledge of the process that produced the data?

We have given the number of successes and the sample size for a simple random sample from a population. In each case, do the following. a. Determine the sample proportion. b. Decide whether using the one-proportion z-test is appropriate. c. If appropriate, use the one-proportion z-test to perform the specified hypothesis test. x=8, n=40, $H_{0}$: p=0.3, $H_{\mathrm{a}}$: p<0.3, $\alpha=0.10$,

Fill in the blanks. a. A relative-frequency distribution is to a variable as a _____ distribution is to a random variable. b. A relative-frequency histogram is to a variable as a _____ histogram is to a random variable.

The carbon monoxide level in a city is predicted to be $0.02 x^{3 / 2}+1$ ppm (parts per million), where x is the population in thousands. In t years the population of the city is predicted to be $x(t)=12+2 t$ thousand people. Therefore, in t years the carbon monoxide level will be $P(t)=0.02(12+2 t)^{3 / 2}+1$ ppm. Find $P^{\prime}(2)$, the rate at which carbon monoxide pollution will be increasing in 2 years.

An investment grows at 24% compounded monthly. How many years will it take to: a. double? b. increase by 50%?

Determine whether each infinite geometric series converges or diverges. If it converges, find its sum. $\sum_{j=0}^{\infty}\left(-\frac{1}{2}\right)^{j}$