Here's the link to the sample AZ MERIT TEST ITEMS.
To view/practice the math items click the math tab and then the link to the student version of the test.
It's a good idea to practice the 3rd grade test as well, since they only give us 5 sample items per grade so far. If it's on the third grade test those skills will probably also be on the 4th grade test.
If you want a challenge try the 5th grade test too!
The website says they will be adding more sample test items soon.