Answer:
X ≥9 years after 2009.
Step-by-step explanation:
Y=4x+4
Y-4=4x
X=(Y-4)/4
Y=number of U.S. households, in millions.
Y≥40
Y-4≥36
(Y-4)/4≥9
So, X≥9.
Answer:
The train need to leave Portland at 03:27 am
Step-by-step explanation:
step 1
Find out how long it takes the train to travel from Portland, Oregon, to Los Angeles, California
Remember that
The speed is equal to divide the distance by the time
so
The time is equal to divide the distance by the speed
Let
s ---> the speed in miles per hour
d ---> the distance in miles
t ---> the time in hours

we have


substitute

step 2
Adds 30 minutes (time it takes to get from the train station to her aunt's house)
Remember that


Convert to minutes

step 3
Remember that

Convert to minutes

Subtract 993 minutes from 1,200 minutes

Convert to hours+minutes


so


therefore
The train need to leave Portland at 03:27 am
Answer:

Step-by-step explanation:

To get
you needed to divide the numerator and denominator by 3.
1 gallon = 2.93
2 gallons = 5.86
3 gallons = 8.86
Therefore the correct table is D.
Answer:
The p value for this case would be given by:
For this case since the p value is higher than the significance level we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 31.3 MPG
Step-by-step explanation:
Information given
represent the sample mean
represent the population standard deviation
sample size
represent the value that we want to test
represent the significance level for the hypothesis test.
z would represent the statistic
represent the p value
Hypothesis to test
We want to test if the true mean is equal to 31.3 MPG, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
Since we know the population deviation, the statistic is given by
(1)
Replacing we got:
The p value for this case would be given by:
For this case since the p value is higher than the significance level we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true mean is not significantly different from 31.3 MPG