Answer = a) add them
When you multiply terms you add the exponents
Answer:
And we can find this probability with thie difference:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
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 heights 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 thie difference:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
Answer:
k
Step-by-step explanation:
x=0 y=6
x=1 y=4
x=2 y=2
x=3 y=0
x=4 y=-2
x=5 y=-4
u basically get the pattern
Answer:
<u><em>y=7 </em></u><u>number of hours at grocery store</u>
<u><em>x=18 </em></u><u>number of hours at baby- sitting</u>
Step-by-step explanation:
According to the information provided.
x is number of hours at baby- sitting
y is number of hours at grocery store
total number of hours worked
<em>1) </em><em>x+y =25</em>
total earn in a week
<em>2) </em><em>x*$6 + y* $9 = $171</em>
<em />
<em>from equation 1</em>
x+y=25
x= 25-y
<em>we place the above derived equation in equation 2 </em>
x*$6 + y* $9 = $171
(25-y)*$6 + y* $9 = $171
(25*6) -6y +9y =171
150+3y=171
3y=171-150
3y=21
<u><em>y=7 </em></u><u>number of hours at grocery store</u>
x= 25-y
x= 25-7
<u><em>x=18 </em></u><u>number of hours at baby- sitting</u>