All our answers lie in the above statement.
Confidence Level:
The creator claims that 9 out 10 students will have the average score in the said range. Or in other words we can say that the creator is 90% confident about the result of the field test. So the confidence level is 90%.
Margin of Error:
The average score lies within 4% of 70%. This means the margin of error is 4% i.e. the average scores can deviate from 70% by 4% .
Confidence Interval:
Lower Limit = 70% - 4% = 66%
Upper Limit = 70% + 4% = 74%
Interpretation:
The exam creator is 90% confident that the average scores of seniors will be between 66% and 74%.
Answer:
Part 1) The explanatory variable is the type of oven
It is a categorical variable
Part 2) The response variable is the baking time
It is a quantitative variable
part 3) two-sample z-test for proportions should be used for the test
Step-by-step explanation:
An explanatory variable is an independent variable that is not affected by all other variables. In this experiment, the type of oven is the input variable and it is not affected by any other variable
A categorical variable is one that has two or more categories without any intrinsic ordering of the categories. The type of oven is either gas or electric, so it is categorical.
A response variable is a dependent variable whose variation depends on other variables. The baking time in this experiment depends on the type of oven used
A quantitative variable is one that take on numerical values.
A two proportion z-test allows you to compare two proportions to see if they are the same. The null hypothesis (H0) for the test is that the proportions are the same. The alternate hypothesis (H1) is that the proportions are not the same.
The answer is,
= 22.5 × 2
= 90 in. squared