一只文具盒的价格是13.15元,一枝钢笔的价格是这只文具盒的3倍.买一枝钢笔和一只文具盒共要多少元钱?
计算下面各题.0.25×4.78×432×1.25+1.25×6810.4﹣9.6×0.53.12+3.12×99.
计算下面各题.7.4×9.91.25×(8×0.8)7.3×4.5﹣28.4.
计算.2.33×5×40.3×0.6×243.65﹣2.2×1.13.7×0.15+4.025.2+3.8×0.934.7×3.5﹣0.2.
用简便方法计算下面各题.(1)2.9×0.45+0.29×4.2+0.029×13(2)3.84×9.6+0.96×61.6.
丽丽遇到一道简算题,百思不得其解,你能帮帮她吗?13.5×10.1+6.5×9.9.