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:
Step-by-step explanation:
Recall that correlation coefficients range from -1 to +1. So, -0.93 is a strong negative relationship. Two interpretations: 1) the correlation is actually very strong, and 2) the correlation is negative. When the correlation is negative, the dependent variable DECREASES when the independent variable INCREASES.
The question is incomplete as the cost price isn't given. However, taking the cost price as x :
Answer:
Kindly check explanation
Step-by-step explanation:
Given :
A car costs$cents when new. It was sold for four fifths of its cost price. How much money was lost on the car.
Let :
Cost price when new = x
Cost price when sold = 4/5 * cost price when new
Cost when sold = 4/5 of x = 4x/5
Amount of money lost on the car = (Cost price of car when new - Cost of car when sold)
Hence,
Amount of money lost on the car = (x - 4x/5)
x - 4x/5 = (5x - 4x) / 5 = x / 5
To obtain the exact price, kindly input the omitted cost when new for x.
Answer:
The length between the two points is RT = 1.3 units
Step-by-step explanation:
The coordinates of the point R and T are R(2,1.2) and T(2,2.5).
Now, by DISTANCE FORMULA:
The distance between two coordinates P and Q with coordinate P(a,b) and Q(c,d) is given as:
So, here the distance RT = 
or, RT = 1.3 units
Hence, the length between the two points is RT = 1.3 units
Answer:
b = ±16
Step-by-step explanation:
Normally to find the number we add to make it a perfect square
We take the coefficient of x
b
Divide by 2
b/2
Then square it
(b/2) ^2
In this case, we are adding 64
(b/2) ^2 = 64
Take the square root of each side
sqrt((b/2) ^2) = sqrt(64)
b/2 = ±8
Multiply each side by 2
b/2*2 = ±8 *2
b = ±16
