Part (a)
P(A) = 0.5
P(B) = 0.4
P(B/A) = 0.6
P(A and B) = P(A)*P(B/A)
P(A and B) = 0.5*0.6
P(A and B) = 0.3
<h3>Answer: 0.3</h3>
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Part (b)
We'll use the result from part (a)
P(A or B) = P(A) + P(B) - P(A and B)
P(A or B) = 0.5 + 0.4 - 0.3
P(A or B) = 0.6
<h3>Answer: 0.6</h3>
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Part (c)
A and B are not independent since P(B) does not equal P(B/A). The fact that event A happens changes the probability P(B). Recall that P(B/A) means "probability P(B) based on event A already happened". A and B are independent if P(B) = P(B/A).
Events A and B are not mutually exclusive since P(A or B) is not zero.
<h3>Answer: Neither</h3>
Better deal normlly means the rate that cost less
rate=cost/amount
9=cost and 3/4 bushel = amount for one store
3/4=0.75
9/0.75=12/1 aka $12/1bushel
9 =cost and 2/3 bushel =amount for another
2/3=about 0.66666
9/0.66666=13.5/1 aka $13.5/1 bushell
compare
12 dollars per bushe vs 13.5 dollar per bushel
12 is cheaper
therefor $9 For 3/4 bushel is better deal
If you sketch the path of the boat, you will form a right triangle towards the port. The distance from the port to the present position is the hypotenuse since it is opposite from the right angle formed by the 12 miles north and 5 miles east movement. Since it is a right triangle, use the Pythagorean Theorem to solve the hypotenuse.
Solution:
h² = o² + a²
h² = 12² + 5²
h² = 144 + 25
h² = 169
√h² = √169
h= 13
The present distance of the boat from the port is 13 miles.
