The probability of lightning striking a person standing near a tower is 30%. The probability that a person dies if lightning strikes is 15%. What is he probability that a person standing near the...

The probability of lightning striking a person standing near a tower is 30%. The probability that a person dies if lightning strikes is 15%. What is he probability that a person standing near the tower dies?

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted on

The probability of lighting striking the person standing near the tower is 30%. If lightning strikes, the probability that the person will die is 15%.

To determine the probability of the person dying we need to calculate the product of the probability of being struck by lightning and the probability of death if that happens.

This is equal to 0.3*0.15 = 0.045 = 0.45%

There is a 4.5% probability that a person standing near the tower dies.

lisamueller | Student, Grade 11 | (Level 2) eNoter

Posted on

The way I would do it is start big: Start with the 30%. You are then told that 15% of people struck by lightening die. So I make the 30% behave like 100% and find 15% of the 30: 30/20 gives 1.5 (5% of 30) 1.5 x 3 gives 4.5 (15% of 30) Therefore the probability of dying from being struck by lightening, standing next to a tower is 4.5%