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分解再相加 = cerakin dan tambah 把金额分成整千和剩下的部分，两部分分别乘七，再把两个积加起来。这样每一步都是容易的乘法。也可以用竖式检查，两种方法结果应该一样。 例子：3 × RM4 120 = 3 × RM4 000 + 3 × RM120 = RM12 000 + RM360 = RM12 360。 注意：零头那一部分也要乘，而且要乘得准确，最容易出错的就是这一部分。

break up and add = cerakin dan tambah Split the amount into whole thousands and the rest, multiply each part by 7, then add the two products. Every step is then an easy multiplication. Check with the column method; both ways must agree. Example: 3 × RM4 120 = 3 × RM4 000 + 3 × RM120 = RM12 000 + RM360 = RM12 360. Watch out: the smaller part must be multiplied too, and carefully; it is where mistakes usually happen.

整数乘十 = darab sepuluh 整数金额乘十，每个数字都往左移一位，个位补上一个零。也可以想成小数点往右移一格。乘十以后金额一定变大，但只大十倍。 例子：10 × RM3 450 = RM34 500。 注意：乘十只补一个零；补两个零是乘一百，小数点往左移是除以十。

multiplying a whole amount by 10 = darab sepuluh When a whole ringgit amount is multiplied by 10, every digit moves one place left and a zero fills the ones, the same as moving the point one place right. The amount must get bigger, but only ten times bigger. Example: 10 × RM3 450 = RM34 500. Watch out: × 10 adds only one zero; two zeros is × 100, and moving the point left is ÷ 10.

乘两位数 = darab dua digit 十六可以分成十和六。先用六去乘金额，写在第一行；再用十去乘，写在第二行（末尾有零）；两行加起来就是积。也可以用竖式或格子法，结果要一样。 例子：15 × RM1 200 = 5 × RM1 200 + 10 × RM1 200 = RM6 000 + RM12 000 = RM18 000。 注意：第二行是乘十，不是乘一。

multiplying by two digits = darab dua digit 16 can be split into 10 and 6. Multiply the amount by 6 for the first row, then by 10 for the second row (it ends in 0), and add the two rows. The column method or the lattice method must give the same result. Example: 15 × RM1 200 = 5 × RM1 200 + 10 × RM1 200 = RM6 000 + RM12 000 = RM18 000. Watch out: the second row is × 10, not × 1.

凑整法 = cara cepat 四十九接近五十，可以先算五十份，再减去多算的一份。五十份可以这样算：先乘一百，再除以二。最后从五十份里减去一份金额。 例子：39 × RM100 = 40 × RM100 − RM100 = RM4 000 − RM100 = RM3 900。 注意：算完五十份不要停，还要减去一份；减的是一份金额，不是减一令吉。

a quick way = cara cepat 49 is close to 50, so work out 50 lots and take away the one extra. For 50 lots, multiply by 100 and then divide by 2. Finally subtract one lot of the amount. Example: 39 × RM100 = 40 × RM100 − RM100 = RM4 000 − RM100 = RM3 900. Watch out: do not stop at 50 lots; take away one lot of the amount, not RM1.

应用题 = masalah 二十四台一样价钱的冷气机，要用乘法：台数乘一台的价钱。一千八百九十九接近一千九百，可以先乘一千九百，再减去二十四台各多算的一令吉。也可以直接用竖式乘两位数。 例子：12 × RM999 = 12 × RM1 000 − 12 × RM1 = RM12 000 − RM12 = RM11 988。 注意：每一台都多算了一令吉，所以最后要减去的是台数那么多令吉，不是只减一令吉。

a word problem = masalah 24 air conditioners at the same price means multiplying the number of units by the price of one. RM1 899 is close to RM1 900, so multiply by RM1 900 and take away the RM1 over-counted on each unit. The column method for two digits also works. Example: 12 × RM999 = 12 × RM1 000 − 12 × RM1 = RM12 000 − RM12 = RM11 988. Watch out: every unit was over-counted by RM1, so subtract as many ringgit as there are units, not just RM1.