'The concession stand at baseball field sells regular drinks for S3 and souvenir drinks for $5. At one game, a total of 75 drinks are sold, earning $255. How many of each type of drink is sold?

Let's use algebra to solve this problem.

Let's represent the number of regular drinks sold as R and the number of souvenir drinks sold as S.

We can set up two equations based on the information given:

1) R + S = 75 (total number of drinks sold)
2) 3R + 5S = 255 (total earnings from drinks sold)

Now, let's solve the system of equations:

From the first equation, we can express R in terms of S: R = 75 - S.

Substitute this into the second equation:

3(75 - S) + 5S = 255
225 - 3S + 5S = 255
2S = 30
S = 15

Now, substitute S back into R = 75 - S:

R = 75 - 15
R = 60

Therefore, 60 regular drinks and 15 souvenir drinks were sold.