Part a: For variable X using z score you have (x-30)/10, replace X for this expression in (a), i mean Z=2+10((x-30)/10) = 2+x-30= put this in the way of z score = (x-18)/1, so the mean is 18 and standard deviation is 1.
Part b: Z=X+Y= (x-30)/10 + (x-20)/8 = solve adding fractions = (18x-440)/80 now divide all the numbers between 18 (because you need to show as z score way) = (x-24.4)/4.4, so the mean is 24.4 and standard deviation is 4.4.
For part c,do the same.
Answer:
(0,0)
Step-by-step explanation:
x y
-2 -8
-1 0
0 0
1 -2
2 0
3 12
Answer:
78.88%
Step-by-step explanation:
We have been given that
The z-score formula is given by
For
For
Now, we find the corresponding probability from the standard z score table.
For the z score -1.25, we have the probability 0.1056
For the z score 1.25, we have the probability 0.8944
Therefore, the percent of the trees that are between 20 and 30 years old is given by
0.8944 - 0.1056
= 0.7888
=78.88%
Answer: (4,6)
Explanation:
x - 3y = -14
x - y = -2
Multiply a -1 to the first equation so the x’s can cancel out.
-x + 3y = 14
x - y = -2
Subtract the two equations together.
2y = 12
y=6
Now, plug in y to one of the original equations.
x - (6) = -2
x=4
Therefore, the answer is: (4,6)
Interest = p times R times T