Final answer:
Alaina sold 9 wreaths for the chorus fundraiser.
Step-by-step explanation:
To find the number of wreaths that Alaina sold, we can set up an equation using the given information. Let's represent the number of wreaths as 'x'. The cost of each wreath is $27. Since Alaina sold 15 poinsettias for $543, we can write the equation as:
27x + 20(15) = 543
Simplifying the equation gives us:
27x + 300 = 543
Now, we can solve for 'x' by isolating it on one side:
27x = 543 - 300
27x = 243
x = 9
Therefore, Alaina sold 9 wreaths for the chorus fundraiser.