Each drink costs $3.25 and each popcorn costs $8.
Explanation:
Step 1:
Assume each drink costs x dollars and each popcorn costs y dollars.
From the given data, we can write the following equations;
, take this as equation 1,
, take this as equation 2.
Step 2:
We multiply equation 2 with 4 so we can cancel out the variable x in both equations. By doing this we get
, take this as equation 3. When we subtract 3 from 1, the x variable is canceled out and y can be calculated.

Step 3:
Substituting this value of y in any of the previous equations we will get x's value.
Here this value of y is substituted in equation 1.
,

So we have x = $3.25 and y = $8. So each drink costs $3.25 and each popcorn costs $8.