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:
= 103 - 3n
Step-by-step explanation:
there is a common difference between consecutive terms , that is
97 - 100 = 94 - 97 = 91 - 94 = - 3
This indicates the sequence is arithmetic with explicit equation
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
here a₁ = 100 and d = - 3 , then
= 100 - 3(n - 1) = 100 - 3n + 3 = 103 - 3n
Answer:
-24
Step-by-step explanation:
Answer: 1) You forgot to change the sign over there. You have to subtract over there.
2) Just be careful while solving equations while changing the signs
