diff --git a/README.md b/README.md
index 9729d30a225dd3479497da455d85155313455fbc..779401a6bee56274c1ac821416ac04b51feb16f0 100644
--- a/README.md
+++ b/README.md
@@ -144,5 +144,5 @@ db.orders.aggregate([{$group : {_id :{"id":"$customer.id", "pseudo":"$customer.p
 ### requête 7
 
 ```js
-db.orders.aggregate([{$unwind:"$items" }, {$group:{_id:"$items.vendor", "total":{$sum: {$multiply: ["$items.finalprice", "$items.qty"]}}}}])
+db.orders.aggregate([{$unwind:"$items" }, {$group:{_id:"$items.vendor", "total":{$sum: "$items.finalprice"}}}])
 ```