Answer:
And we can find this probability with the normal standard distirbution or excel and we got:
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 lenghts of a population, and for this case we know the distribution for X is given by:
Where 
and 
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability with the normal standard distirbution or excel and we got:
Answer:
Um sorry if its wrong but I think its that it gets bigger as you go on.
Step-by-step explanation:
Answer: she has 17 CDs now.
Step-by-step explanation:
The total number of CDs that Chen had initially is 17.
She gives 2 to her brother. This means that she would be having
17 - 2 = 15
She buys 4 more. It means that she would be having
15 + 4 = 19
Her brother gives her 1. So the number that she has is
19 + 1 = 20
she gives 3 to her best friend. Therefore, the number of CDs that Chen has now is
20 - 3 = 17
Answer:
Step-by-step explanation:
3x+y+1=0
2x-y+4=0
Answer:
C. 3
Step-by-step explanation:
The constant of proportionality is the slope (or rate of change) of the graph.
To find the equation of the graph;
Take points (1,3) and (3,9)
The slope (m) = change in y ÷ change in x
m = 
Taking another point (x,y) on the graph;
m = 
y - 3 = 3x - 3
y = 3x + 0
y = 3x
This can be expressed as;
y ∝ 3x
Which means that as y rises, x rises too but 3 remains the same. The value 3 is the constant of proportionality in this relationship.
