Answer:
3/8
Step-by-step explanation:
1. Display your knowledge to the problem
You know that a whole pizza must be 8/8 slices, right? And you know that Justin ate 1/4 of the pizza and Dan ate 3/8. Good, that's all you need to know so far.
2. Add 1/4 and 3/8
You have to figure out how much they ate all together. First, find a common denominator. Let's do... hmmm, 8 is perfect! 3/8 is already in its simplest form but what about 1/4? Well, 1/4 is 2/8 in simplest form. There we go! And 3/8 plus 2/8 is 5/8!
3. What's left of the pizza?
Well, we have 5/8 eaten and in whole, there's 8 slices, so that must mean 3 slices are still there and haven't been eaten yet! 3 slices = 3/8
Hope that helps!