Rod's original addition method was:

$38 + 44 + 52 = 82 + 52 = 134$

Another way to add the bills could be by pairing the numbers differently. For instance:

$(38 + 52) + 44 = 90 + 44 = 134$

This approach reorganizes the way the numbers are grouped but still leads to the same total.

Do you have any questions or would you like more details? Here are some related questions:

1. What is the associative property of addition?
2. How can changing the order of addition help in faster calculations?
3. Can Rod add the grocery bills in reverse order and still get the same result?
4. What are some other examples of adding numbers with different groupings?
5. What is the commutative property of addition?

Tip: Grouping numbers that are easy to add first can simplify mental math.