How does the weakness or strength of currency affects exchange rate and how do you know which currency is strong or weak?

The strength or weakness of a currency affects exchange rates by determining how much of one currency can be exchanged for another; a strong currency can buy more of another currency, while a weak currency buys less. Currency strength is typically assessed through factors like economic indicators, interest rates, and market demand. A strong currency is often indicated by higher purchasing power and stability, while a weak currency may show signs of inflation or economic instability. Tools such as the Big Mac Index or currency exchange rates can help gauge a currency's relative strength.