Question

in a2-b2 trials of a random experiment , if an event A happens a+b times then the probablity of happening of event A is given by

Answer 1

sample space, n(S)=a²-b²
event A    n(A)=a+b
probability,p(A)=$\frac{n(A)}{n(S)}$
                        =$\frac{a+b}{ a^{2}- b^{2} }$
                        =$\frac{a+b}{(a+b)(a-b)}$
                        =a-b 

Answer 2

Answer:

The probability of happening of event A is given by  $\frac{1}{a-b}$

Step-by-step explanation:

Given:

No. of trials = a² - b²

Happening of event A = a + b

We need to find the probability of happening of event A

We know that probability = $\frac{Event Happening}{Total Happening}$

                                          = $\frac{a+b}{a^2-b^2}$

We know that a² - b² = (a - b) (a + b)

Therefore, substituting the values, we get,

Probability = $\frac{a+b}{(a-b)(a+b)}$

                  = $\frac{1}{a-b}$

Therefore, the probability of happening of event A is given by  $\frac{1}{a-b}$