We will estimate the risk of getting, hence dying, from a disease-inducing-serving of beef during the British "Mad Cow Epidemic". We will estimate this risk by using the ratio of the number of disease-inducing-servings of beef caused by the epidemic to the total number of beef servings produced by Britain during the epidemic.
Let us first determine our denominator. Using this data we find that the United Kingdom produces about (1000)(1000) tonnes of beef for consumption each year. Using a conversion table this is (1000)(1000)(.9842)(2240) pounds or rather about 2(10^9) pounds. Let us assume that a serving is about 1/2 a pound. Then the British beef industry produces about (2)(2)(10^9) servings of beef a year. This epidemic lasted at least five years. Hence their were at least (5)(2)(2)(10^9) servings of beef produced.
Now let us estimate our numerator. Recall, there were about 140 deaths attributed to diseased cow meat during the Mad Cow Epidemic in Britain. Hence of the 5(2)(2)(10^9) servings of beef, we will estimate about 140 were disease inducer.
From these estimates, the chance that a given serving of beef being is a disease-inducing-serving is about 140/((5)(2)(2)(10^9))=70/(10^10), or rather a bit less than 100/(10^10) = 1/(10^8).
Discussion Questions:
1. Discuss the relevance of this computation to the current U.S. "Mad Cow Scare".
2. Discuss the assumptions we made in order to interpret such our ratio as a chance.
3. Discuss the assumptions we made in order to estimate this ratio's numerator and this ratio's denominator.
4. Discuss whether or not it is reasonable to consider our estimate a worst case scenario worst case scenario.