Let events
A=Nathan has allergy
~A=Nathan does not have allergy
T=Nathan tests positive
~T=Nathan does not test positive
We are given
P(A)=0.75 [ probability that Nathan is allergic ]
P(T|A)=0.98 [probability of testing positive given Nathan is allergic to Penicillin]
We want to calculate probability that Nathan is allergic AND tests positive
P(T n A)
From definition of conditional probability,
P(T|A)=P(T n A)/P(A)
substitute known values,
0.98 = P(T n A) / 0.75
solving for P(T n A)
P(T n A) = 0.75*0.98 = 0.735
Hope this helps!!
For this case what you should know is that both functions are of the potential type.
We have then that
y = 2 * 2 ^ x This function grows exponentially upwards.
y = -2 * 5 ^ x This function grows exponentially downwards.
Answer See attached graphics.
1)4-8=-4
2)3+4-5=2
3) -13
4)8+12=20
5) -14
:) Well, I dunno about anyone else but this question makes my head spin!