Answer: X=9
Step-by-step explanation:
Answer:
Symbolab - Math Solver is a good calculator that shows you steps.
Answer:

And we can use the following formula:

And replacing the info we got:

Step-by-step explanation:
We define two events for this case A and B. And we know the probability for each individual event given by the problem:


And we want to find the probability that A and B both occurs if A and B are independent events, who menas the following conditions:


And for this special case we want to find this probability:

And we can use the following formula:

And replacing the info we got:
