#### Answer

The bills should be grouped in stacks of 10.

#### Work Step by Step

A person has 310 five dollar bills and 460 ten dollar bills. He wants to group the bills in equal size stacks with the same type of bill in each stack.
This can be accomplished by finding the Greatest Common Factor (GCD) of 310 and 460. This GCD will be the number of bills per stack.
We can find the GCD by prime factoring 310 and 460.
310 = 2 x 5 x 31
460 = 2 x 2 x 2 x 3 x 5
The common factors of the two are: 2 x 5 = 10
Therefore, we can have stacks of 10 bills. There will be 31 stacks of five dollar bills and 46 stacks of ten dollar bills.