Answer:
The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159
Step-by-step explanation:
According to the given data we have the following:
mean = μ= 22
standard deviation = σ = 2
n = 100
μx = 22
σx=σ/√n=2/√100=0.2
Therefore, P( x < 21.8)=P(x-μx)/σx<(21.8-22)/0.2
=P(z<-1)
= 0.159
The probability that the average age of a randomly selected sample of 100 students will be less than 21.8 years is 0.159
None of those answers are correct sadly.
Answer:
62 miles per hour/62 mph
Step-by-step explanation:
Shania drives at a CONSTANT rate, which means in the 5 hours it took her to drive, each hour she drove the same amount.
So we need to do 310 miles in 5 hours, which is:
310/5
Solving this, we get:
62
The answer is 62 miles per hour.
Happy learning!
Area of a square with side s is

In your question, the side or s is:

And so the area of a square with that side length would be:

And using this formula:

We get that the area is:

And simplifying that we get the final answer as:
We have a rectangle with length L that is 3 inches more than the width W. Then we can write this as:

The area of the rectangle is 180 square inches.
We have to find the width W.
As the area is equal to the product of the length and the width, we can write this equation and solve for W as:

We have a quadratic equation. The roots of this equation will be the mathematical solutions.
We can find the roots using the quadratic formula:
![\begin{gathered} W=\frac{-b\pm\sqrt[]{b^2-4ac}}{2a} \\ W=\frac{-3\pm\sqrt[]{3^2-4\cdot1\cdot(-180)}}{2\cdot1} \\ W=\frac{-3\pm\sqrt[]{9+720}}{2} \\ W=\frac{-3\pm\sqrt[]{729}}{2} \\ W=\frac{-3\pm27}{2} \\ W_1=\frac{-3-27}{2}=-\frac{30}{2}=-15 \\ W_2=\frac{-3+27}{2}=\frac{24}{2}=12 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20W%3D%5Cfrac%7B-b%5Cpm%5Csqrt%5B%5D%7Bb%5E2-4ac%7D%7D%7B2a%7D%20%5C%5C%20W%3D%5Cfrac%7B-3%5Cpm%5Csqrt%5B%5D%7B3%5E2-4%5Ccdot1%5Ccdot%28-180%29%7D%7D%7B2%5Ccdot1%7D%20%5C%5C%20W%3D%5Cfrac%7B-3%5Cpm%5Csqrt%5B%5D%7B9%2B720%7D%7D%7B2%7D%20%5C%5C%20W%3D%5Cfrac%7B-3%5Cpm%5Csqrt%5B%5D%7B729%7D%7D%7B2%7D%20%5C%5C%20W%3D%5Cfrac%7B-3%5Cpm27%7D%7B2%7D%20%5C%5C%20W_1%3D%5Cfrac%7B-3-27%7D%7B2%7D%3D-%5Cfrac%7B30%7D%7B2%7D%3D-15%20%5C%5C%20W_2%3D%5Cfrac%7B-3%2B27%7D%7B2%7D%3D%5Cfrac%7B24%7D%7B2%7D%3D12%20%5Cend%7Bgathered%7D)
The solutions are W = -15 and W = 12.
The first one is not valid, as W has to be greater than 0.
Then, the solution to our problem is W = 12 in.
Answer: the width is W = 12 inches.