We have been given that the distribution of the number of daily requests is bell-shaped and has a mean of 38 and a standard deviation of 6. We are asked to find the approximate percentage of lightbulb replacement requests numbering between 38 and 56.
First of all, we will find z-score corresponding to 38 and 56.
Now we will find z-score corresponding to 56.
We know that according to Empirical rule approximately 68% data lies with-in standard deviation of mean, approximately 95% data lies within 2 standard deviation of mean and approximately 99.7% data lies within 3 standard deviation of mean that is 
.
We can see that data point 38 is at mean as it's z-score is 0 and z-score of 56 is 3. This means that 56 is 3 standard deviation above mean.
We know that mean is at center of normal distribution curve. So to find percentage of data points 3 SD above mean, we will divide 99.7% by 2.
Therefore, approximately 
of lightbulb replacement requests numbering between 38 and 56.
last one. i can do the first part. put x = distance from top of ladder to the floor, y = distance from base of ladder to the wall (draw a picture) then pythagoras sez
<span><span>x2</span>+<span>y2</span>=25</span>
calculus says
<span>2x<span>x′</span>+2y<span>y′</span>=0</span>
and you are told that
<span><span>y′</span>=2</span>
so you know
<span>2x<span>x′</span>+4y=0</span>
or
<span><span>x′</span>=−<span><span>2y</span>x</span></span>
Answer:
That exterior angle is equal to 87 degrees.
Step-by-step explanation:
In order to find the measure of the exterior angle, we start by trying to find x. We can do this by adding up the 3 interior angles and setting them equal to 180. The first angle is equal to 43. The second angle is equal to x + 15. The third angle is equal to 180 - 3x (which we know because the angle and 3x is equal to 180). So we set equal to 180.
43 + (x + 15) + (180 - 3x) = 180 ----> Combine like terms.
238 - 2x = 180 -----> Subtract 238
-2x = -58 ----> Divide by -2
x = 29
Now that we have the x value, we can plug into the exterior angle measure to get the value.
3x = 3(29) = 87 degrees
It is a quadratic
where x-8 is the squared term
do
x-8=u
u^2-13u+30=0
solve
u=
u=
u=
u=
u=
u=
or u=
u=10 or 3
10=x-8 or 3=x-8
18=x or 11=x
x=11 and/or 18
Answer:50 customers would be expected to buy birthday cards next month.
Step-by-step explanation:
Last month customers at a gift shop bought 40 birthday cards, 19 congratulation cards, 20 holiday cards, 21 thank you cards. The total number of greeting cards that the customers bought last month would be
40 + 19 + 20 + 21 = 100
Percentage of customers that bought birthday cards last month would be
40/100 × 100 = 40%
supposed 125 customers by greeting cards next month, the expected number of customers that would buy birthday cards next month would be
40/100 × 125 = 50
