Question

Betty has several of the standard six-sided dice that are common in many board games. If Betty rolls one of these dice, what is the probability that she rolls a three? use 3 decimal places.

Answer 1

1/6 = 0.167

Answer 2

A dog allergy test for people has a 90% accuracy rate. Only 1% of the population has an allergy to dogs (actually it is much smaller than that!). Assume a major pet food manufacturer purchases this test and administers it to 1,000 employees.

(Test is +) (-) (Total)
Has Allergy:
Not Allergy:
Total:

Answer 3

A dog allergy test for people has a 90% accuracy rate. Only 1% of the population has an allergy to dogs (actually it is much smaller than that!). Assume a major pet food manufacturer purchases this test and administers it to 1,000 employees.

~~~~~~~~~~~(Test is +) (-) (Total)
Has Allergy:
Not Allergy:
Total:

Answer 4

LOL this is why it is so hard to do this sort of test
more positives will be due to that 10% wrong accuracy problem than due to having allergy.

out of 1000 people, 10 have allergy
out of these 10 who have it
.9 * 10 = 9 test positive correctly
1 gets missed

out of the 990 who do not have allergy .10 *990 = 99 test positive incorrectly

get it?

Answer 5

did you get from such a simple first problem to the problem that messes up people who write papers on this sort of thing ?

Answer 6

A dog allergy test for people has a 98% accuracy rate. Only 1% of the population has an allergy to dogs (actually it is much smaller than that!). Use a group of 100,000 people who've taken this test and the information provided to complete a table and answer the following question:

If you tested negative, what is the probability you have a dog allergy?