Word Problems!!!!
posted by Candy Corn .
Help with the following problems:
1. Leah bought 2 boxes of cookies. She ate 3 and found that she had 21 left. How many cookies were in each box?
2. Arturo built 3 sandcastles with 6 towers each. Paco built 5 sandcastles with 4 towers each. Who built more towers? How many more?
3. Ashley has 35 dollars. She wants to buy 4 bags of peanuts at 2 dollars each. How much money will she have left?
Please solve all or at least ONE of the problems. Thanks!

I'll do the first one.
2x  3 = 21
2x = 21 + 3
2x = 24
x = 24/2
x = 12
I'll be glad to check your answers to the other problems.