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计算排法 = kira susunan 整数减分数，要先从整数借 1，写成“几又四分之四”再减；接着把二分之一换成四分之几，再加上去。按从左到右的次序做。 例子：2 − 1/3 + 1/6 = 1又6/6 − 2/6 + 1/6 = 1又5/6。 注意：二分之一和四分之几相加前，要先换成相同的分母。

work out the arrangement = kira susunan To take a fraction from a whole number, borrow 1 and write it as quarters over quarters before subtracting. Then change 1/2 into quarters and add. Work from left to right. Example: 2 − 1/3 + 1/6 = 1 6/6 − 2/6 + 1/6 = 1 5/6. Watch out: change halves into quarters before adding them.

找被减的卡 = cari kad yang ditolak 在 □ − □ + □ 里，另外两张卡都是加上去的（前面的数和后面的数都算进总数），只有中间那张被减掉。所以只要试：把两张卡相加，再减去第三张，看哪一次得到题目的结果。先把三张卡换成相同的分母（十二分之几）会比较好算。 例子：卡 1/2、1/4、1/8 要得 5/8：1/2 + 1/4 − 1/8 = 5/8，所以被减的是 1/8。 注意：交换前面和后面两张卡，结果不变，所以要问的是“哪一张被减”。

find the card that is subtracted = cari kad yang ditolak In □ − □ + □, the cards in the outer two boxes both count towards the total, and only the card in the middle box is taken away. So try each card as the one subtracted: add the other two and subtract it, and see which gives the target. Changing all cards to twelfths makes this easier. Example: cards 1/2, 1/4 and 1/8 with target 5/8: 1/2 + 1/4 − 1/8 = 5/8, so 1/8 is subtracted. Watch out: swapping the two outer cards gives the same result, which is why we ask which card is subtracted.

为什么换分母 = mengapa tukar penyebut 想一想：分数相加或相减时，分子代表“有几份”，只有每一份大小相同，份数才能直接加减。把一个分数换成等值分数，分子和分母乘同一个数，大小不会改变。 例子：2/3 换成 4/6，还是同样大小的一块，只是切成更小的份。 注意：等值分数的分子和分母要乘同一个数；先想清楚要换成哪一个分母再换。

why change the denominator = mengapa tukar penyebut Think about it: when adding or subtracting fractions, the numerator counts parts, and parts can only be counted together when they are the same size. Changing to an equivalent fraction multiplies the top and bottom by the same number, so the size does not change. Example: 2/3 changed into 4/6 is the same amount, cut into smaller parts. Watch out: multiply the numerator and denominator of an equivalent fraction by the same number, and decide which denominator you need before changing.