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两步运算链 = rantai dua langkah 先做开头那个箭头的除法，得到 P；再用 P 去做下一个箭头的乘法，得到 Q。每一步只用前一步的得数，不能回头用最开始的数。 例子：45 → ÷ 5 → 9 → × 100 → 900。 注意：跳过除法，直接拿开头的数去乘，是常见的错误。

a two-step chain = rantai dua langkah Do the division on the first arrow to get P, then use P for the multiplication on the next arrow to get Q. Each step uses only the result of the step before; do not go back to the starting number. Example: 45 → ÷ 5 → 9 → × 100 → 900. Watch out: skipping the division and multiplying the starting number is a common mistake.

倒推 = kerja ke belakang 知道乘完以后的结果，要找原来的数，就做相反的运算：乘的反面是除。用结果除以箭头上的数，得到的就是 X。再把它乘回去检查。 例子：Y → × 5 → 350，Y = 350 ÷ 5 = 70。 注意：倒推时要用相反的运算，不能再乘一次。

work backwards = kerja ke belakang We know the result after multiplying and want the starting number, so do the opposite operation: the opposite of multiplying is dividing. Divide the result by the number on the arrow to get X, then multiply back to check. Example: Y → × 5 → 350, so Y = 350 ÷ 5 = 70. Watch out: working backwards needs the opposite operation; do not multiply again.

合并步骤 = gabungkan langkah 乘一百会在末尾补两个 0，除以十会去掉一个 0。把这两步合起来看：一共补了几个 0、去了几个 0，最后多出几个 0？多出一个 0 等于乘十，多出两个等于乘一百。 例子：7 先乘十、再除以十，补一个 0 又去一个 0，没有多出 0，结果还是原来的 7。 注意：乘和除的 0 会互相抵消，先数清楚再回答。

combine the steps = gabungkan langkah Times one hundred adds two zeros and dividing by ten removes one. Put the two steps together: how many zeros were added, how many removed, and how many are left over? One extra zero is the same as times ten; two extra zeros are the same as times a hundred. Example: 7 times ten and then divided by ten gains one zero and loses one, so none is left over and the result is 7 again. Watch out: zeros added by multiplying and removed by dividing cancel out, so count carefully before answering.