Assume that the chances of a patient having a heart attack is 40%. It is also assumed that a meditation and yoga course reduce the risk of heart attack by 30% and prescription of certain drug reduces its chances by 25%. At a time a patient can ch

Assume that the chances of a patient having a heart attack is 40%. Assuming that a meditation and yoga course reduces the risk of heart attack by 30% and prescription of certain drug reduces its chance by 25%. At a time a patient can choose any one of the two options with equal probabilities. It is given that after going through one of the two options, the patient selected at random suffers a heart attack. Find the probability that the patient followed a course of meditation and yoga. Interpret the result and state which of the above stated methods is more beneficial for the patient.

Suppose that of all used cars of a particular year, 30% have bad brakes. You are considering buying a used car or that year. You take the car to a mechanic to have the brakes checked. The chance that the mechanic will give you wrong report is 20%. Assuming that the car you take to the mechanic is selected at random from the population of cars of that year. The chance that the car's brakes are good given that the mechanic says its brakes are good is-

On a certain day the chance of rain is 80% in Delhi and 30% in Hyderabad.Assume that the chance of rain in the two cities is independent. What is the probability that it will not rain in either city?

The percentage change in the time period of a second pendulum when its amplitude is reduced by 30% is (assume theta is very small)