Question 1112110
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Such problems were solved, probably, 20 times before in this forum.


Therefore, instead of writing 21-th solution, I prepared for you the list of links.


Looking in these solutions, you will find your way to solve it on your own.



https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.932415.html

https://www.algebra.com/algebra/homework/Finance/Finance.faq.question.411605.html

https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.383965.html

https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1097231.html