A magazine printed photos of three celebrities along with three photos of the celebrities as babies. The baby pictures did not identify the celebrities. Readers were asked to match each celebrity with the correct baby pictures. What probability that a reader guesses at random will match three
The first question is a basic probability calculation. The answer is $$\frac{1}{3}\times\frac{1}{2}\times\frac{1}{1}=\boxed{\frac{1}{6}}$$
This second one is a typical derangement problem. The answer is $$\frac{D_3}{3!} = \frac{1}{2!} - \frac{1}{3!}=\boxed{\frac{1}{3}}$$