Answer:
a) 20.16; b) 20.49 and 21.51
Step-by-step explanation:
We use z scores for each of these. The formula for a z score is
.
For part a, we want the 20th percentile; this means we want 20% of the data to be lower than this. We find the value in the cells of the z table that are the closest to 0.20 as we can get; this is 0.2005, which corresponds with a z score of -0.84.
Using this, 21 as the mean and 1 as the standard deviation,
-0.84 = (X-21)/1
-0.84 = X-21
Add 21 to each side:
-0.84+21 = X-21+21
20.16 = X
For part b, we want the middle 39%. This means we want 39/2 = 19.5% above the mean and 19.5% below the mean; this means we want
50-19.5 = 30.5% = 0.305 and
50+19.5 = 69.5% = 0.695.
Looking these values up in the cells of the z table, we find those exact values; 0.305 corresponds with z = -0.51 and 0.695 corresponds with z = 0.51:
-0.51 = (X-21)/1
-0.51 = X-21
Add 21 to each side:
-0.51+21 = X-21+21
20.49 = X
0.51 = (X-21)/1
0.51 = X-21
Add 21 to each side:
0.51+21 = X-21+21
21.51 = X
Answer: (A) H0: μ = 140 mg vs. H1: μ ≠ 140 mg
Step-by-step explanation:
Usually null hypothesis represents the claim that the values associated to the groups being tested have no statistical difference but alternative hypothesis supports the claim that there is statistical difference.
Let be the population mean .
We are given that the mean potassium content of a popular sports drink is listed as 140 mg in a 32-oz bottle.
i.e. Null hypothesis :
Alternative hypothesis for two tail hypothesis has sign (≠).
i.e. Alternative hypothesis :
∴ The hypotheses for a two-tailed test of the claimed potassium content:
H0: μ = 140 mg vs. H1: μ ≠ 140 mg
Answer:
x= 18.5 y = 14.2
Step-by-step explanation:
Answer:
1. Translation 3 units to the right;
2. Reflection across the x-axis;
3. Translation 4 units up.
Step-by-step explanation:
First, rewrite the function in following way:
Apply such transformations:
1. Translate the graph of the parent function 3 units to the right to get the graph of the function
2. Reflect the graph of the function across the x-axis to get the graph of the function
3. Translate the graph of the function 4 units up to get the graph of the function