You have three $1 bills, four $5 bills, and two $10 bills in your wallet. You select a bill at random. Without replacing the bill, you choose a second bill at random. What is P($10 then $1)?
You have 9 bills in total in your wallet
You have 2 in 9 chances of pulling out $10 since you only have 2 bills. Now for $1, you have 3 bills but since there is no replacement, you have one less bill since you already picked out $10. So you will have 3 in 8 chances of getting $1.