Answer:
Step-by-step explanation:
Hello!
The mean is a measurement of central tendency that shows what is the most expected value of the variable. The standard deviation is a measurement of variability, it shows you how distant or dispersed are the values of a certain population or sample in regards to the value of the mean.
In this example the variable is X: score obtained on a math test.
It's mean is μ= 52 and its standard deviation is σ= 10
To know how many standard deviations away is a value of X concerning the mean you have to first subtract the mean to the value of X, X - μ, and then you have to divide it by σ:
(X - μ)/ σ
If X=76
(76 - 52)/ 10= 2.4
The score obtained by Andrea is 2.4σ away from the mean.
I hope it helps!
cos (arctan (1))=
arctan (1) = 45 take it to the third quadrant = add 180 = 225
cos (225) = -1 / sqrt(2)
never leave a sqrt in the denominator
= -1 /sqrt(2) * sqrt(2)/sqrt(2)
= -sqrt(2)/2
sin (arccos (1/2)
arccos (1/2) = 60 take it to the 4th quadrant -60 degrees
sin (-60)
- sin 60
- sqrt(3)/2
J because the x value is used more then once.
V that is potential diff is equal to current multiplied by resistance. This snows that v is proportional to current directly
solution:
I choose 5 women from a pool of 10 in 10C2 ways.
I choose 5 men from a pool of 12 in 12C2 ways.
So total number of ways of choosing in 10C2 x 12C2. Now I need to arrange them in 5 pairs. This is where I have a different solution. The solution says that there are 5! ways to arrange them in pairs.
But I cant seem to understand why? My reasoning is that for first pair position I need to choose 1 man from 5 and 1 woman from 5. So for the first position I have 5 x 5 choices (5 for man and 5 for woman). Similarly for the second position I have 4 x 4 choices and so on. Hence the total ways are 5! x 5!
So I calculate the total ways as 10C2 * 12C2 * 5! * 5!. Can anyone point the flaw in my reasoning for arranging the chosen men and women in pairs.
