Probability that both roads from a to b are blocked is the product of the individual probabilities, i.e.
P(~ab)=0.25*0.25=0.0625
Similarly
P(~bc)=0.25*0.25=0.0625
Probability that EITHER one or both of ab and bc are blocked is the sum of the probabilities:
P(~ab ∪ ~bc)=0.0625+0.0625=0.125
(recall that one cannot travel from a to c if either ab or bc is blocked.)
Therefore the probability that there exists an open route from a to c
= P(ac) = 1-P(~ab ∪ ~bc)
= 1 - 0.125
=0.875
one thing that may help is the use of diagrams. See the attached photo.
To solve you need two equations.
2w + 2L = 22
L = w + 3
2w + 2(w + 3) = 22
2w + 2w + 6 = 22
4w + 6 = 22
4w = 16
w = 4
L = w + 3
L = 4 + 3
L = 7
Answer:
(5, -3)
y= -3
x= 5
Step-by-step explanation:
-x-2y=1
x+y=2
solve the equation
-x-2y=1
x=2-y
substitute the value of x into an equation
-(2-y)-2y=1
remove parenthesis
-2-y-2y=1
subtract y to 2y
-2-y=1
add 2 from both sides
-y=3
divide both sides by -y
y= -3
substitute the value of y into an equation
x=2-(-3)
remove parenthesis
x=2+3
add 2 to 3
x=5
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(5,-3)
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Answer:
N= 2, 12, 16, 20....
Step-by-step explanation: