Answer:
18 3/4
Step-by-step explanation: You would simply subtract 26 5/8 - 7 7/8. You would have to make 26 5/8 into an improper fraction 25 13/8 and subtract that by 7 7/8 to equal 18 6/8 which you would then simplify into 18 3/4.
Set Events:
T=tests positive~T=tests negativeP=subject is pregnant~P=subject is not pregnant
We are givenP(T n ~P)=0.02P(~T n P)=0.03P(P)=0.7
recall by definition of conditional probabilityP(A|B)=P(A n B)/P(B)
Need to find P(P|~T)
First step: make a contingency diagram of probabilities (intersection, n)
P ~P sum
T 0.67 0.02 0.69=P(T)
~T 0.03 0.28 0.31=P(~T)
sum 0.70 0.30 1.00
=P(P) =P(~P)
therefore
P(P|~T)=P(P n ~T)/P(~T)=0.03/0.31 [ both read off the contingency table ]
=0.0968
There are two triangles here: ABC and ADF. These triangles are similar, and thus proportional. So, we can set up a proportion between the left side of each triangle and the base of each triangle.
AB / AD = BC / DE
4 / (4 + BD) = 5 / 9
---AD is made up of AB and DB. We know AB, but not BD, so we need to find its value to find the length of AD.
5(4 + BD) = 9 x 4
20 + 5BD = 36
5BD = 16
BD = 3.2
AD = AB + BD
AD = 4 + 3.2
AD = 7.2
Hope this helps!
Answer:
Expected winnings for one spin = 0.1
Step-by-step explanation:
Expected Value = Sum of [(Probability of X)(Value of X)]
E(X) = Σ [P(X).X]
Two Events : X = +68 , P(X) = 1/38 and X = -2 , P(X) = 37/38
E(X) = [(68) (1/38)] + [(-2)(37/38)]
[(68)(0.03)] + [(-2)(0.97)]
= 2.04 - 1.94
= 0.1