Wednesday Math Problems – do you have any to solve?

numbersHere are this week’s problems to get your math mind working.  After you’ve given these a try, maybe you can make your own problem up for the rest of us to solve.  Leave your problem in a comment so we’ll have lots to do.  Happy “mathing!”

I had $1.00.  I went to the story to buy 2 pencils.  Each pencil cost 29 cents.  How much did the pencils cost in all?  How much change did I get back?  Show two possible combinations that I might have received as change.

Sam counts his marble collection.  When he round the number of marbles to the nearest hundred it is 500.  When he rounds the number to the nearest ten it is 470.  How many marbles might Sam have?   Explain your thinking.

You add a 3-digit number to 234 in your head without using pencil and paper.  What might the 3-digit number be?  WHat made it easy to do in your head?