Answer:
0.1274
Step-by-step explanation:
Let X be the random variable that measures the number of children who get their own coat.
Then, the expected value of X is
E[X] = 1P(X=1) + 2P(X=2)+3P(X=3)+...+10P(X=10)
The probability that a child gets her or his coat is
P(X=1) = 1/10
To compute the probability that 2 children get their own coat, we notice that there are 10! possible permutations of coats. The two children can get their coat in only one way, the other 8 coats can be arranged in 8! different positions, so the probability that 2 children get their own coat is
P(X=2) = 8!/10! = 1/(10*9) and
2P(X=2) = 2/(10*9)
Similarly, we can see that the probability that 3 children get their own coat is
P(X=3) = 7!/10! = 1/(10*9*8) and
3P(X=3) = 3/(10*9*8*7)
and the expected value of X would be
E[X] = 1/10 + 2/(10*9) + 3/(10*9*8)+...+10/10! = 0.1274
Answer:
C I think
Step-by-step explanation:
Answer:
-4(5 + 7g) = -28g -20
O is the midpoint so both sides FO and OG need to equal each other.
3x + 17 = 7x - 15
Subtract 3x from both sides:
17 = 4x -15
Add 15 to both sides:
32 = 4x
Divide both sides by 4:
x = 32/4
X = 8
Now you have the value of X, solve for the lengths:
FO = 3x +17 = 3(8) +17 = 24 +17 = 41
OG = 7x -15 = 7(8) -15 = 56-15 = 41
Total length would be 41 + 41 = 82
