Tickets for the baseball games were $2.50 for general admission and 50 cents for kids. If there were six times as many general admissions sold as there were kids tickets, and the total receipts were $7750, how many of each type of ticket were sold?

There was 3000 general admission tickets sold and 500 kid ticket sold.

How did I get this?

First, we need to see what information we have.
$2.50 = General admission tickets = (G)
 $0.50 = kids tickets =  (K)
There were 6x as many general admission tickets sold as kids. G = 6K

We need two equations:
G = 6K  
$2.50G + $.50K = $7750
Since, G = 6K we can substitute that into the 2nd equation.

2.50(6K) + .50K = 7750
Distribute 2.50 into the parenthesis

15K + .50K = 7750
combine like terms

15.50K = 7750
Divide both sides by 15.50, the left side will cancel out.

K = 7750/15.50
K = 500 tickets
So, 500 kid tickets were sold.

Plug K into our first equation (G = 6k)

G = 6*500
G = 3000 tickets

So, 3000 general admission tickets were sold,

Let's check this:

$2.50(3000 tickets) = $7500 (cost of general admission tickets)
$.50(500 tickets) = $250 (cost of general admission tickets)
$7500 + $250 = $7750 (total cost of tickets)