Out of 5,400 raffle tickets sold at the carnival, 180 are winners.
at this same rate, how many winning raffles tickets can be expected if 8,100 raffle tickets are sold?

This how my teacher helped me understand a problem like this. You are looking for a percentage to plug in. This percentage will be represented by x. To make it easier you can think of the equation as a sentence and then plug in the signs:

180 IS what percent OF 5400
       Which would translate mathematically to:
180 = x * (Multiply) 5400

Then you solve for x!
x = 180/5400
x = 0.0333333 which would equal roughly 3% (move decimal 2 places right).

Then plug it into your new equation:
3% OF 8100 IS what? y will represent our final answer.

(You should convert the percent back to decimal form though. or just keep it there, it was easier for me to understand when i converted it)

y = 0.033 * 8100
y = 270 winning tickets.

IF I'M NOT MISTAKEN

Aquadratic function is one of the form f(x)=ax2 + bx + c l, where a,b, and c are numbers with are not equal to zero.