Simplify the following:
(25/a - a l)/(a + 5)
Put each term in 25/a - a l over the common denominator a: 25/a - a l = 25/a - (a^2 l)/a:
(25/a - (a^2 l)/a)/(a + 5)
25/a - (a^2 l)/a = (25 - a^2 l)/a:
Answer: ((25 - a^2 l)/a)/(a + 5)
A sample size of 60 is required.
We use the formula
We first find the z-score associated with this level of confidence:
Convert 99% to a decimal: 99/100 = 0.99
Subtract from 1: 1-0.99 = 0.01
Divide by 2: 0.01/2 = 0.005
Subtract from 1: 1-0.005 = 0.995
Using a z-table (http://www.z-table.com) we see that this value is equally distant from 2.57 and 2.58; therefore we will use 2.575:
Answer:
b. 2-independent sample t-test
Correct for this case is the best test since the result from each group are independent and we can compare the sample means between th two groups
Step-by-step explanation:
For this case the intention is try to test if scores on a test of science achievement differ for female and male 8th grade students. let's analyze the possible options for this case:
a. 2-dependent sample t-test
False is not possible since the nature of the gender is not possible to conclude tha the results from boys and girls are dependent
b. 2-independent sample t-test
Correct for this case is the best test since the result from each group are independent and we can compare the sample means between the two groups
c. Correlation
False we can't compare the means of interest with a correlation coefficient since that's not the purpose of the study
d. 2-way ANOVA
False we have just one variable between two groups so is not possible to apply a 2 way ANOVA
Answer: $14.0
Step-by-step explanation:
For us to calculate this question, we have to find 20% of $17.45 and then subtract the value gotten from $17.45. This will be:
= $17.45 - (20% × $17.45)
= $17.45 - (0.2 × $17.45)
= $17.45 - $3.49
= $13.96
= $14.0 to nearest cent
