The exchange rate between the US dollar and the Nigerian naira fluctuates constantly. To determine how much a 100-dollar Play Store gift card is in naira, one needs to check the current exchange rate.

Typically, the conversion is based on the market rate at the time of the transaction. Financial institutions and currency exchange platforms provide the most accurate rates. For example, if the exchange rate is 1 dollar = x naira, then a 100-dollar gift card would be worth 100 times that exchange rate in naira.
It's important to note that exchange rates can change due to various factors such as economic conditions, central bank policies, and global market trends. So, it's advisable to stay updated on the latest rates to get the most precise value of the 100-dollar Play Store gift card in naira.