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:
Perimeter = 10x + 8 units.
Area = 6x^2 + 13x - 5 units^2.
Step-by-step explanation:
The perimeter is 2*length + 2*breadth
= 2(2x + 5) + 2(3x - 1)
= 4x + 10 + 6x - 2
= 10x + 8 units.
The area = length * breadth
= (2x + 5)(3x - 1)
= 6x^2 - 2x + 15x - 5
= 6x^2 + 13x - 5 units^2.
Answer:
<u>Secant</u>: a straight line that intersects a circle at two points.
<u>Intersecting Secants Theorem</u>
If two secant segments are drawn to the circle from one exterior point, the product of the measures of one secant segment and its external part is equal to the product of the measures of the other secant segment and its external part.
From inspection of the given diagram:
- M = Exterior point
- MK = secant segment and ML is its external part
- MS = secant segment and MN is its external part
Therefore:
⇒ ML · MK = MN · MS
Given:
- MK = (x + 15) + 6 = x + 21
- ML = 6
- MS = 7 + 11 = 18
- MN = 7
Substituting the given values into the formula and solving for x:
⇒ ML · MK = MN · MS
⇒ 6(x + 21) = 7 · 18
⇒ 6x + 126 = 126
⇒ 6x = 0
⇒ x = 0
Substituting the found value of x into the expression for KL:
⇒ KL = x + 15
⇒ KL = 0 + 15
⇒ KL = 15
Equation: L=P*R*T
P=100
R=1.5%=0.015
T=5
Multiply and you get 7.5 as the interest.