incorrect query aggregation result
I have a query with aggregation result incorrect as following:
Quantity Price Amount
2 100 200
3 50 150
result 5 150 750
From above, you can see that query result 750 is calculated by aggregating quantity and price accordingly and then muliply them after aggregation. However, price can not be aggregated and the correct query result for amount should be 200+150=350.
How can I get the correct result? Please advise. Thanks.