To solve this, let's assign letters to the soda and popcorn. To keep it simple, let's make those letters "s" and "p."
We know that the amount paid for the soda plus the amount paid for the popcorn equals $12.25.
s + p = $12.25
Now, here's the trick. The problem tells us that the popcorn cost $1.25 more than the soda. So:
p = s + $1.25
We can substitute that into our original equation, like this:
s + (s + $1.25) = $12.25
2s + $1.25 = $12.25
2s = $11.00
s = $5.50
So the soda cost $5.50. If the popcorn cost $1.25 more than the soda, it must have cost $6.75 because $5.50 + $1.25 = $6.75.
Let's check to see if that's right:
p + s = $12.25
$6.75 + $5.50 = $12.25
Yes, we are right - the popcorn cost $6.75.
