[問題]PP3 test2 DS

[doggyface922]

DS
If 500 is the multiple of 100 that is closest to X and 400 is the multiple of 100 that is closest to Y, which multiple of 100 is closest to X+Y ?
(1) x < 500
(2) y < 400

請問這題是在問蝦米啊? 題目看不懂 (汗.....)

[Cortilia]

DS
If 500 is the multiple of 100 that is closest to X and 400 is the multiple of 100 that is closest to Y, which multiple of 100 is closest to X+Y ?
(1) x < 500
(2) y < 400

請問這題是在問蝦米啊? 題目看不懂 (汗.....)

我試試看把我的想法表達一下,但手邊沒有答案,無法確認想法是否正確
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500 is the multiple of 100 that is closest to X
化做式子我會表達成 450<X<550
400 is the multiple of 100 that is closest to Y
化做式子我會表達成 350<Y<450
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當X<500時
450<X<500 且 350<Y<450, 所以 800<X+Y<950
故,800.900都有可能為multiple of 100 that is closest to X+Y
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當Y<400時
450<X<550 且 350<Y<400, 所以 800<X+Y<950
故,800.900都有可能為multiple of 100 that is closest to X+Y
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當X<500 且 Y<400時
450<X<500 且 350<Y<400, 所以 800<X+Y<900
故,800.900都有可能為multiple of 100 that is closest to X+Y
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所以答案是不是E呢?
因為三種情況都無法確認是800還是900,得出確切一數字
有錯請指正
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狗要變成牛很簡單,只要相信自己是牛,然後把狗狗的外衣給脫下來,牛牛就出現了

[doggyface922]

答案是E沒錯..(忘了po答案...呵呵)

謝謝可愛的Cortilia 清楚又詳細的解答....
好心的你一定會有好報的...