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六年級(jí)奧數(shù)工程問題及答案

時(shí)間:2014-10-08 18:08:00   來源:無憂考網(wǎng)     [字體: ]

【編輯寄語】以下是©無憂考網(wǎng)為大家整理的《六年級(jí)奧數(shù)工程問題及答案》,供大家參考!


1、一件工作。甲隊(duì)做2天,乙隊(duì)做5天,共完成4/15;甲5天,乙2天,共完成19/60,問甲、乙兩隊(duì)單獨(dú)做各需要多少天?

2、A、B兩地相距22.4千米。有一支*隊(duì)伍從A出發(fā),向B勻速前進(jìn);當(dāng)*隊(duì)伍隊(duì)尾離開A時(shí),甲,乙兩人分別從A,B兩地同時(shí)出發(fā)。乙向A步行;甲騎車先追向隊(duì)頭,追上隊(duì)頭后又立即騎向隊(duì)尾,到達(dá)隊(duì)尾后再立即追向隊(duì)頭,追上隊(duì)頭后又立即騎向隊(duì)尾……當(dāng)甲第5次追上隊(duì)頭時(shí)恰與乙相遇在距B地5.6千米處;當(dāng)甲第7次追上隊(duì)頭時(shí),甲恰好第一次到達(dá)B地,那么此時(shí)乙距A地還有多少千米?

1、一件工作。甲隊(duì)做2天,乙隊(duì)做5天,共完成;甲5天,乙2天,共完成,問甲、乙兩隊(duì)單獨(dú)做各需要多少天?


解答:(19/60-4/15)÷3 = 1/60

(19/60+4/15)÷7=1/12

(1/12+1/60)÷2 = 1/20

(1/12-1/60)÷2 = 1/30

甲:1÷1/20 =20(天) 乙:1÷1/30=30(天)

2、A、B兩地相距22.4千米。有一支*隊(duì)伍從A出發(fā),向B勻速前進(jìn);當(dāng)*隊(duì)伍隊(duì)尾離開A時(shí),甲,乙兩人分別從A,B兩地同時(shí)出發(fā)。乙向A步行;甲騎車先追向隊(duì)頭,追上隊(duì)頭后又立即騎向隊(duì)尾,到達(dá)隊(duì)尾后再立即追向隊(duì)頭,追上隊(duì)頭后又立即騎向隊(duì)尾……當(dāng)甲第5次追上隊(duì)頭時(shí)恰與乙相遇在距B地5.6千米處;當(dāng)甲第7次追上隊(duì)頭時(shí),甲恰好第一次到達(dá)B地,那么此時(shí)乙距A地還有多少千米?

解答:設(shè)甲每次從隊(duì)尾追到隊(duì)頭行x千米,從隊(duì)頭到隊(duì)尾行y千米,

5x-4y=22.4-5.6 2x-2y=5.6 解得x= 5.6 y=2.8

相遇時(shí),甲實(shí)際行5.6×5+2.8×4=39.2(千米),乙行5.6千米,39.2÷5.6=7

甲到B,實(shí)際行5.6×7+2.8×6=56(千米),乙行5.6÷7=8(千米)

乙距A:22.4-8=14.4(千米)