问题 解答题 口算 568+167=______978-87=______800-571=______15×6÷9=______800-239=______51÷17=______91÷7=______72-72÷6=______. 答案 568+167=735978-87=891800-571=22915×6÷9=10800-239=56151÷17=391÷7=1372-72÷6=60故答案为:735,891,229,10,561,3,13,60.