A shape-shifting alien race called the Skrell are planning to invade Earth.
They have placed a number of spies in human form in the small English town of Giggleswick so they can learn how to behave
like humans for the main invasion.
The Skrell spies currently make up 3 percent of the Giggleswick population.
It has been found that 79 percent of the spies cannot roll their tongues.
However, it is known that 13 percent of Humans also cannot roll their tongues.
What is the probability that someone who cannot roll their tongue is not an alien spy?
What is the probability that someone who can roll their tongue is an alien spy?
You must get both answers right to pass this SOB.
The probability that someone who cannot roll their tongue is really human is 0.842.
The probability that someone who can roll their tongue is really Skrell is 0.007.