Answer:
(A) 0.297
(B) 0.595
Step-by-step explanation:
Let,
H = a person who suffered from a heart attack
G = a person has the periodontal disease.
Given:
P (G|H) = 0.79, P(G|H') = 0.33 and P (H) = 0.15
Compute the probability that a person has the periodontal disease as follows:

(A)
The probability that a person had periodontal disease, what is the probability that he or she will have a heart attack is:

Thus, the probability that a person had periodontal disease, what is the probability that he or she will have a heart attack is 0.297.
(B)
Now if the probability of a person having a heart attack is, P (H) = 0.38.
Compute the probability that a person has the periodontal disease as follows:

Compute the probability of a person having a heart attack given that he or she has the disease:

The probability of a person having a heart attack given that he or she has the disease is 0.595.
No. 1
x=2
y=0
Solve it by substitution method
Where,
y=2-x
and replace y at equation 1
This is what it looks like.
Answer:
the first option
Step-by-step explanation:
a and d, b and c
This may be a little complicated, but basically, you have to break everything down into decimals. 21.5 X .25 = 5.375. Subtract 5.375 from 21.5 and you should get 10.75 or 10 3/4. Divide 10 3/4 by 1/4, the answer should be 30 burgers.