0.15 as fraction or multiply 3/8 and 2/5
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
To find the GCF:
-- List the factors of the first number.
-- List the factors of the second number.
-- Make a short list of the factors that show up for BOTH numbers.
-- Find the biggest number on the short list.
Factors of the first number (99): <u>1</u>, 3, 9, <u>11</u>, 33, 99 .
Factors of the second number (121): <u>1</u>, <u>11</u>, 121 .
Short list (factors that show up for both numbers): 1, 11
Biggest number on the short list: <em>11</em>
