王老师买了8盒糖和5盒蛋糕共用去l71元,李老师买了同样的5盒糖和2盒蛋糕共用去90元.每盒糖和每盒蛋糕各多少元?
计算下面各题,能简算的要简算.2.52×2.8+7.48×2.8 2.05÷0.82+37.6 69.6÷3.2÷2.5.
3.6÷1.5÷2 1.6×(6.42﹣3.92)+0.64(4.08×4.5+0.78)÷8.7 7.2×6.32+4.68×7.2﹣7.2.
脱式计算(能简算的要简算)0.25×1.53×4 3.7×0.72+0.28×3.7 3.5×10.1 19.2÷(0.25×3)
用简便方法计算下面各题.(1)4.7×10.2(2)0.88×4.9+5.1×0.88(3)2.5×8×0.4×0.125(4)(30.5﹣15.64﹣12.36)×0.4.
怎样算简便就怎样算.6.45+1.36﹣6.45+7.64 2.7×(100+2) 9.64﹣7.3﹣0.74.63÷[(9.6+2.2)﹣7.17] 0.5×2.5×4.