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:
Conjecture : 2xy / ( x + y ) ≤ √xy
Step-by-step explanation:
Harmonic mean of x and y = 2xy/( x + y )
<u>Formulate a conjecture about their relative sizes </u>
we will achieve this by computing harmonic and geometric means
Geometric mean = √xy
harmonic mean = 2xy/( x + y )
Conjecture : 2xy / ( x + y ) ≤ √xy
attached below is the proof
Answer:
x = 89
Step-by-step explanation:
The sum of the angles of a triangle add to 180 degrees
x+32+ 59 = 180
Combine like terms
x + 91 = 180
Subtract 91 from each side
x +91-91= 180-91
x = 89
-0.10416 /.going on forever
The circumference when the diameter is 18 = 18pi
The circumference when the diameter is 6 = 6pi
18pi/6pi=3
The circumference will become a third of what it was.
Hope this helps!
