3. According to the results of the football tournament, it is known that in each match, one of the teams scored either twice as many or half as many goals as its opponent. Can the total number of goals scored be equal to 2020?
Solution: The number of goals scored in each match is divisible by 3. Therefore, the total number of goals scored should also be divisible by 3, but 2020 is not divisible by 3.

Answer: no.