Answer:
If a woman in a particular country has a 2/5 chance of developing cancer at some point in her life, the odds in favor of an American woman developing cancer can be calculated by dividing the probability of developing cancer by the probability of not developing cancer. The probability of developing cancer is 2/5, and the probability of not developing cancer is 3/5 because the sum of the probabilities of an event occurring and not occurring is 1.
Therefore, the odds in favor of an American woman developing cancer are 2/3. This means that for every 2 women who develop cancer, there are 3 women who do not develop cancer.
Similarly, the odds against an American woman developing cancer can be calculated by dividing the probability of not developing cancer by the probability of developing cancer. The odds against are 3/2, which means that for every 3 women who do not develop cancer, there are 2 women who develop cancer.