Kristin has 12 stickers. Amber has 4 more stickers than Kristin. Erin has 2 fewer stickers than Amber. How many stickers does Erin have.

Joe has 12 oranges. He gives one to each of his brothers and one to each of his 2 sisters. He has 8 oranges left. How many brothers does Joe have?

There are 27 boys and 13 girls at the park. Then 18 boys leave the park. How many boys are at the park now?

Omar buys a dozen oranges at the market. He uses 5 of them to make juice. How many oranges does Omar have left?