Answer:
Step-by-step explanation:
Area of a circle is pi r squared.
So 3.142 times the radius squared.
They gave you the diameter(d), that's the distance all the way across. You need the radius(r), which is one half of the diameter. 7 divided by 2.
3.142X3.5squared=
Well, 3.5 squared is 3.5X3.5=12.25
So, then 3.142X12.25=38.4895
Now, we round. Second decimal place is an eight, followed by a nine. Five or above means round up.
38.49
Answer:
P(X≥75)= 0.22663
Step-by-step explanation:
Hello!
The variable has a normal distribution with mean μ= 67 and a standard deviation δ= 8.
X~N(μ;δ²)
You need to find the probability that a randomly selected X value is at least 75, i.e. 75 or more, symbolically:
P(X≥75)
To calculate this probability is best to work using the standard normal distribution. This distribution is derived from the normal distribution. Considering a random variable X with normal distribution, mean μ and variance δ², the variable Z =(X-μ)/δ ~N(0;1) is determined.
The standard normal distribution is tabulated. Any value of any random variable X with normal distribution can be "converted" by subtracting the variable from its mean and dividing it by its standard deviation.
Using the formula and the values of the parameters of the population you have to standardize the value of X
Z= (X-μ)/δ = (75 - 67)/ 8= 0.75
Now you can express the probability under the standard normal distribution:
P(X≥75) = P(Z≥0.75)
The Z-tables show probability values P(Z≤z₁₋α)= 1 - α, then:
P(Z≥0.75)= 1 - P(Z<0.75)= 1 - 0.77337= 0.22663.
I hope it helps!
Answer:
The lines are perpendicular
Step-by-step explanation:
we have
![2x+y=4](https://tex.z-dn.net/?f=2x%2By%3D4)
isolate the variable y
----> equation A
The slope of the line A is ![m=-2](https://tex.z-dn.net/?f=m%3D-2)
-----> equation B
The slope of the line B is ![m=\frac{1}{2}](https://tex.z-dn.net/?f=m%3D%5Cfrac%7B1%7D%7B2%7D)
Remember that
If two lines are perpendicular, then their slopes are opposite reciprocal (the product of their slopes is equal to -1)
In this problem
The slopes of line A and line B are opposite reciprocal
therefore
The lines are perpendicular
Answer:
umm
Step-by-step explanation: