#import "@local/handout:0.1.0": * #show: handout.with( title: [Warm-Up: Tuesday], by: "Mark", ) #problem() Charlie has two children. \ One of them is a boy born on a Tuesday. \ What is the probability that Charlie has two boys? #solution([ $13 / 27$, which notably isn't $1/2$. #v(2mm) Draw a $14 times 14$ square, highlight the possible cases, and you'll see it. \ #v(2mm) Order is very important in this problem. \ If we knew that the _first_ child was a boy born on Tuesday, the probability of two boys would be $1/2$. \ Also consider a smaller case where a week has two days. ])