Answer:
a. Sage and Tom have the same number of talk minutes left on their cell phone plans.
b. y = x - 7
Explanation:
Sage talked for 7 minutes with her dad.
Tom talked for 4 minutes with a friend and 3 more minutes with his mom which means he spoke for :
= 4 + 3
= 7 minutes
They both spoke for 7 minutes and therefore have the same amount of time left.
Algebraic expression:
Assuming the time Tom started with is denoted by x and the time he is left with is denoted by y.
The expression is:
y = x - 7
Answer:


Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the grade points avergae of a population, and for this case we know the following properties
Where
and
The empirical rule, also referred to as the three-sigma rule or 68-95-99.7 rule, is a statistical rule which states that for a normal distribution, almost all data falls within three standard deviations (denoted by σ) of the mean (denoted by µ). Broken down, the empirical rule shows that 68% falls within the first standard deviation (µ ± σ), 95% within the first two standard deviations (µ ± 2σ), and 99.7% within the first three standard deviations (µ ± 3σ).
So we can find the z score for the value of X=3.44 in order to see how many deviations above or belowe we are from the mean like this:

So the value of 3.44 is 2 deviations above from the mean, so then we know that the percentage between two deviations from the mean is 95% and on each tail we need to have (100-95)/2 = 2.5% , because the distribution is symmetrical, so based on this we can conclude that:

Answer:
AX = 14
Step-by-step explanation:
The medians of a triangle intersect at its centroid.
The position of the centroid X from the vertex A is
AX =
AL =
× 21 = 14
Well each piece of the whole is what made the whole... so in that case each piece is little 1/4's of the whole....
3000x + 1000y < 30000
2000x + 6000y < 30000
x = 7.5
y = 7.5