Question

7．甲、乙兩隊(duì)合修一條路，甲隊(duì)修了全長(zhǎng)的$\frac{3}{8}$，甲隊(duì)比乙隊(duì)少修了全長(zhǎng)的幾分之幾？

Answer 1

分析 將全長(zhǎng)當(dāng)作單位“1”，甲隊(duì)修了全長(zhǎng)的$\frac{3}{8}$，根據(jù)分?jǐn)?shù)減法的意義，乙隊(duì)修了全長(zhǎng)的1-$\frac{3}{8}$，則用乙隊(duì)修的占全長(zhǎng)的分率，減去甲隊(duì)修的占全長(zhǎng)的分率，即得甲隊(duì)比乙隊(duì)少修了全長(zhǎng)的幾分之幾．

解答 解：1-$\frac{3}{8}$-$\frac{3}{8}$
=$\frac{5}{8}$-$\frac{3}{8}$
=$\frac{1}{4}$
答：甲隊(duì)比乙隊(duì)少修了全長(zhǎng)的$\frac{1}{4}$．

點(diǎn)評(píng) 本題考查了學(xué)生完成簡(jiǎn)單的分?jǐn)?shù)減法應(yīng)用題的能力．