Question

A door alarm works in 72 out of 100 cases and surveillance camera works in 68 out of 100 cases. What is the probability of effective screening techniques keeping in mind that these two methods can be used together? 0.49 0.72 0.68 0.89

Answer 1

Secondary SchoolMath 5+3 pts

The door alarm works in 72 out of 100 cases. And the surveillance camera works in 68 of 100 cases.

Let us assume two events:

Event A and Event b

Then we can get the Probability of the two events:

P(A) = 0.68

P(B) =0.72

Now, we have to find the probability that our screening technique would work together. That is, we have to find the probability that both the door alarm and surveillance camera would work in a specific case.

In mathematical terms, we have to find P(A \cap B)

Both A and B are independent events. Because, the happening of Event A is not related to B. And similarly, the happening of Event B is not related to Event A.

The door alarm and surveillance camera work independently.

So, we can write:

P(A\cap B) = P(A) . P(B) \\ \\ \implies P(A \cap B) = 0.72 \times 0.68 \\ \\ \implies \boxed{\bold{P(A\cap B) = 0.4896}}

Answer 2

The final answer is ,

《0.4896》