To find the difference between how much Anna ate and how much her brother ate, we need to subtract the portion her brother ate (38) from the portion Anna ate (58).
The correct equation to show the difference is:
58 - 38 = 20
However, since we're working with fractions, we would write this as:
5/8 - 3/8 = 2/8, which simplifies to 1/4.
In the options provided, the correct equation showing this difference in standard form is:
58 - 38 = 20.