What is the total value of cancelled orders?
total value = SUM(MULTIPLY(quantityOrdered, priceEach)); cancelled orders refers to status = 'Cancelled';
SELECT SUM(T1.quantityOrdered * T1.priceEach) FROM orderdetails AS T1 INNER JOIN orders AS T2 ON T1.orderNumber = T2.orderNumber WHERE T2.status = 'Cancelled'