Bad gums may mean a bad heart. Researchers discovered that 80% of people who have su ered a heart attack had periodontal disease, an inammation of the gums. Only 30% of healthy people have this disease. Suppose that in a certain community heart attacks are quite rare, occurring with only 10% probability. If someone does not have periodontal disease, what is the probability that he or she will have a heart attack?

0.069 = 6.9% probability that he or she will have a heart attack

Step-by-step explanation:

Conditional Probability

We use the conditional probability formula to solve this question. It is

In which

P(B|A) is the probability of event B happening, given that A happened.

is the probability of both A and B happening.

P(A) is the probability of A happening.

In this question:

Event A: Does not have periodontal disease

Event B: Has a heart attack.

Probability of not having a periodontal disease:

100 - 80 = 20% of 10%(had a heart attack).

30% of 100-10 = 90%(did not have a heart attack). So

Intersection of A and B:

Not having the disease, suffering a heart attack, so 20% of 10%.

What is the probability that he or she will have a heart attack?

0.069 = 6.9% probability that he or she will have a heart attack

x=-2

infinite number of lines, so there is an infinite number of equations.

step-by-step explanation:

there are an infinite number of line that passes through the point (-2,5)

x=-2   is one line that passes through the point

y = 5 is another line that passes through the point

(these two lines are perpendicular to each other).

since the number of   numbers are infinite and the slope is the ratio of two numbers,(change in y over change in x) we can have an infinite number of slopes.     our only condition is that it passes through the point (-2,5)

question: how many people can she serve?

answer: she can serve 16.66666667 people. so she can only give 16 people a complete serving.

question: does she have enough ice cream for her guests?

answer: no. explanation: she only has enough for 16 people to have a full serving. however, she can give a 17th person a partial serving.