A dog allergy test for people 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 do not have a dog allergy?
(Express your answer as decimals rounded to four decimal places.)

It is 0.9990

As is 0.0010 as four decimal places. for those that do have which means the same as a negative probability that you don't but reaffirms the situation so inverse of 0.0010 is needed to be 0.9990. so when added together they can become 100% = 1 whole as a probability that both options equal together 1.

When questions ask it negatively using words like don't, haven't, didn't etc. etc.

This question asks for such probability which is similar to percentage in scale for those that do have an allergy.

If the question asked the probability you do have a non allergy the opposite effect happens and we inverse the answer to 99%

But because it asks negatively that you dont have we keep the establishing number of the actual allergy finding because its the same as if you don't.

1% of 100,000 = 1000

1000/100000 = 1/1000

1/1000 = 0.001

Step-by-step explanation:

Once you find 1/1000 is answer to turn numbers into decimals remember the rule 1 = 100

So if 1 = 100

and we want 1/100

1/100 will equal and simplify into 0.01

Where 1/1000 will equal and simplify into 0.001 as the number 100 is extended another digit so would the decimal.