140 tickets were sold to public and 260 tickets were sold to students
Solution:
Let "p" be the number of tickets sold to public
Let "s" be the number of tickets sold to students
Cost of one ticket sold to public = $ 8.00
Cost of one ticket sold to student = $ 3.00
There were a total of 400 tickets sold
number of tickets sold to public + number of tickets sold to students = 400
p + s = 400 -------- eqn 1
Making a total revenue of 1900.00$
number of tickets sold to public x Cost of one ticket sold to public + number of tickets sold to students x Cost of one ticket sold to student = 1900.00

8p + 3s = 1900 ------ eqn 2
Let us solve eqn 1 and eqn 2 to find values of "p" and "s"
Multiply eqn 1 by 3
3p + 3s = 1200 ---- eqn 3
Subtract eqn 3 from eqn 2
8p + 3s = 1900
3p + 3s = 1200
(-) ------------------
5p = 700
p = 140
Substitute p = 140 in eqn 1
p + s = 400
140 + s = 400
s = 260
Thus 140 tickets were sold to public and 260 tickets were sold to students