# Problem of the Week Problem A Adding and Subtracting

Step 1: Pick two different three-digit numbers. Label the larger number $$A$$ and the smaller number $$B$$.

Step 2: Subtract $$B$$ from $$999$$ and label the difference $$C$$.

Step 3: Add $$A$$ and $$C$$ and label the sum $$D$$.

Step 4: Subtract $$1000$$ from $$D$$ and label the difference $$E$$.

Step 5: Add $$1$$ to $$E$$ and label the sum $$F$$.

1. What is the connection between the number $$F$$ and the numbers $$A$$ and $$B$$?

2. Try the same steps with different numbers. Do you think you will always get the same result? Why or why not?

Themes: Computational Thinking, Number Sense