Answer:
The reason why standard deviation of the entire class is greater than standard deviation of males and females considered separately, is that mean values for males and females are different from each other.
Step-by-step explanation:
The concept of mean is well represented by the following formula
mean = 
, where x1, x2, xn are the observations and N is the number of observations (population).
Standard deviation represents the distance between each observation and the mean of the population (all observations). The formula for this parameter is:
Standard deviation =√[((x1 - x)² + (x2-x)² + ....+ (xn-x)²)/N-1], where x1, x2,..., xn are the observations and x is the mean value.
In this case you have that each height registered is an observation and the number of observations represents the N value. As you can see if the mean for males is different from that of females their standard deviation will be different too. Usually males have heigths greater than that of females (1.77 vs 1.64, in USA for example), and heights inside each group will be more similar than between groups. Then, when you mix all observation there will be an increase in standard deviation, because you are mixing very different heigths
<span>50x - 32x^3
= 2x (25 - 16x^2)
hope that helps</span>
Answer:
2.3
v
−
5
Step-by-step explanation: your welcome
Answer:
For a monthly cost of at least $7 and at most $8, you can have between 100 and 110 calling minutes.
Step-by-step explanation:
The problem states that the monthly cost of a celular plan is modeled by the following function:
In which C(x) is the monthly cost and x is the number of calling minutes.
How many calling minutes are needed for a monthly cost of at least $7?
This can be solved by the following inequality:
For a monthly cost of at least $7, you need to have at least 100 calling minutes.
How many calling minutes are needed for a monthly cost of at most 8:
For a monthly cost of at most $8, you need to have at most 110 calling minutes.
For a monthly cost of at least $7 and at most $8, you can have between 100 and 110 calling minutes.
Answer:
<em>797.0ft²</em>
Step-by-step explanation:
<u>Find a related diagram attached</u>
Area of the gate = Area of the semicircle + Area of the Rectangle
Area of the semicircle = πr²/2
r is the radius
From the diagram, radius r = 20/2 = 10ft
Area of the semicircle = 3.14(10)²/2
Area of the semicircle = 3.14(100)/2
Area of the semicircle = 314/2
Area of the semicircle = 157ft²
Area of the rectangle = Length * Width
Area of the rectangle = 20*32
Area of the rectangle = 640ft²
Area of the gate = 157 + 640
Area of the gate = 797ft²
<em>Hence the area of the gate is 797.0ft²</em>
