Can someone help me understand how interest charges work?

Overview

I have been paying off my statement balance for years. I went on vacation and over budgeted, so I couldn't pay off the full card. Instead of paying the full statement balance of $2,532 due for July, I paid $2000. The remaining $532 I paid before August's due statement posted. I was charged $35 in interest for the month. How is that possible for just $532? Is interest really that expensive? This is the Venture X credit card btw. Thank you! submitted by /u/kellyatta [link] &#32

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