四则运算规则先算乘除后算加减，所以：先算481÷5再把的到的结果乘以7的到673.4然后再248-673.4=-425.4
先算乘除再算加减有乘有除从左向右算248-481 ÷5x7=248-96.2×7=248-673.4=-425.4
248-481 ÷5x7=248-96.2x7=248-673.4=-425.4谢谢，请采纳
