Question

17．甲堆煤重3$\frac{2}{5}$噸，比乙堆煤的$\frac{4}{5}$多0.2噸，兩堆煤一共多少噸？

Answer 1

分析 已知甲堆煤比乙堆煤的$\frac{4}{5}$多0.2噸，甲堆煤減0.2噸即是乙堆煤的$\frac{4}{5}$，用除法即可得乙堆煤的噸數(shù)，再相加即可．

解答 解：（3$\frac{2}{5}$-0.2）÷$\frac{4}{5}$+3$\frac{2}{5}$
=3.2×$\frac{5}{4}$+3$\frac{2}{5}$
=4+3$\frac{2}{5}$
=7$\frac{2}{5}$（噸）
答：兩堆煤一共$7\frac{2}{5}$噸．

點評 本題考查了分?jǐn)?shù)的四則復(fù)合應(yīng)用題，關(guān)鍵是得出甲堆煤減0.2噸即是乙堆煤的$\frac{4}{5}$．