How many XRP to a dollar?

Excuse me, I'm just a bit confused about the exchange rate. Could you please clarify how many XRP correspond to a single dollar? I've been hearing about cryptocurrencies for a while, but I'm still not quite sure about the specifics. It seems like the prices fluctuate quite frequently, so I'm not sure how to calculate the exact amount. Could you help me out with this? It would be really appreciated if you could give me a brief overview or an explanation on how to keep track of these exchange rates.