And how many countries have a red, white and blue flags? 10, 20,30..?
Going by member states of the United Nations, and counting only those flags which have all three colors -- red, white, and blue -- and no other color at all, we find twenty:
Democratic People's Republic of Korea (a/k/a North Korea)
Lao People's Democratic Republic (aka Laos)
United Kingdom of Great Britain & Northern Island
United States of America
If we count Taiwan, which is not a UN member, that would bring the total to twenty one.
Can you match these flags with the countries?