"(" is not valid at this position, expecting EOF, ";"

Question

I have got the following table:

I want to pivot this table with code:

SELECT productLine, productScale, buyPrice 
FROM PRODUCTS
PIVOT (
        AVG(buyPrice)
        FOR productScale
        IN ('1:10', '1:18')
);

But at line 3 of the query, I get an error in the title of this question. What is wrong?