Because when one country interest rates down, they will reduce the attractiveness for investors in that country's currency holdings, and will result in those currencies weaken to 7.
Because when a country cuts interest rates. It will reduce the attractiveness to investors of holding the currency of that country. And will contribute to such currency depreciates it.
Because when a nation to reduce interest rates down. It will reduce the attractiveness to investors in holding the currency of that country. And will result in such currency weakened.