This reminds me of a part in Derren Brown's book Tricks of the Mind. He talks about how we are easily misled by numbers, especially percentages. One shocking example he gave was if you took a test for cancer that was 99% accurate. Even if that test came back positive, statistically you would still be more likely to NOT have cancer. Why? Because mathematically, the chances of ANYONE having cancer at a particular moment are smaller than the chances of the test being wrong.

EDIT: Sorry, I misremembered the bit from the book. Derren didn’t specifically mention cancer. The way it was written in the book spoke about a hypothetical disease. He said that if the disease affects one in 10,000 people, and the test is 99% accurate. But he says that in that situation you’re more likely to not have the disease, even if it came back positive.

Sorry, I’m not sure why I misremembered that as being about cancer. Please accept my apology for getting that wrong.