Math

StatisticsQ&A LibraryTwenty-one independent measurements were taken of the hardness (on the Rockwell C scale) of HSLA-100 steel base metal, and another 21 independent measurements were made of the hardness of a weld produced on this base metal. The standard deviation of the measurements made on the base metal was 3.06, and the standard deviation of the measurements made on the weld was 1.41. Assume that the measurements are independent random samples from normal populations. Can you conclude that measurements made on the base metal are more variable than measurements made on the weld?Question

Asked Feb 23, 2020

1 views

Twenty-one independent measurements were taken of the hardness (on the Rockwell C scale) of HSLA-100 steel base metal, and another 21 independent measurements were made of the hardness of a weld produced on this base metal. The standard deviation of the measurements made on the base metal was 3.06, and the standard deviation of the measurements made on the weld was 1.41. Assume that the measurements are independent random samples from normal populations. Can you conclude that measurements made on the base metal are more variable than measurements made on the weld?

Step 1

According to the given question, twenty-one independent measurements were taken of the hardness (on the Rockwell C scale) of HSLA-100 steel base metal, and another 21 independent measurements were made of the hardness of a weld produced on this base metal. The standard deviation of the measurements made on the base metal was 3.06, and the standard deviation of the...

Tagged in

Find answers to questions asked by student like you

Show more Q&A

Q: In a survey of 3153 adults aged 57 through 85 years, it was found that 86.8% of them used at least...

A: Click to see the answer

Q: Overtime Rule in Football The accompanying table lists results of overtime football games before and...

A: State the test hypotheses. Null hypothesis: H0: The winning and overtime game are independent to eac...

Q: The lengths of human pregnancies are normally distributed with a mean of 268 days and a standard dev...

A: Solution: Let X be the length of human pregnancy. From the given information, X follows normal distr...

Q: group of observations measured at successive time intervals is known as a(n) _____. a. fore...

A: Click to see the answer

Q: If n=12, x¯(x-bar)=47, and s=3, find the margin of error at a 80% confidence level

A: Margin of error (E): The margin of error for sample mean is given by,

Q: A person draws a card from a hat. Each card is one color with the following probabilities of being d...

A: Click to see the answer

Q: #4

A: Click to see the answer

Q: 8. Salaries of 33 college graduates who took a statistics course in college have a mean, x, of $67,...

A: The provided information are:

Q: To construct a confidence interval using the given confidence level, do whichever of the following i...

A: Given data n = 100, σ = 17 n > 100 and population deviation is known. So, we can assume the distr...