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先算左边 = kira kiri dahulu 左边两个金额都知道，先算出左边的值。右边是方框减去一个已知金额，结果要和左边一样。方框在减号前面，所以方框等于左边的值再加上被减去的那个金额。算好后代回右边检查。 例子：RM900 − RM300 = □ − RM100，左边 RM600，□ = RM600 + RM100 = RM700。 注意：左边的值只是中间结果，还不是方框。

work out the left first = kira kiri dahulu Both amounts on the left are known, so work out the left side first. The right side is the box minus a known amount and must give the same value. The box comes before the minus sign, so the box is the left-side value plus the amount taken away. Put it back into the right side to check. Example: RM900 − RM300 = □ − RM100; the left side is RM600, so □ = RM600 + RM100 = RM700. Watch out: the left-side value is only a middle result, not the box.

未知数在左边 = anu di sebelah kiri 这次方框在左边，右边的两个金额都知道，所以先算右边。左边是九千减去方框，结果要等于右边的值。方框是被减去的数，所以用九千减去右边的值就能求出方框。 例子：RM500 − □ = RM700 − RM400，右边 RM300，□ = RM500 − RM300 = RM200。 注意：方框在减号后面，要用减法求；用加法会得到比九千还大的数。

the unknown is on the left = anu di sebelah kiri This time the box is on the left and both amounts on the right are known, so work out the right side first. RM9 000 minus the box must equal that value. The box is the amount taken away, so subtract the right-side value from RM9 000. Example: RM500 − □ = RM700 − RM400; the right side is RM300, so □ = RM500 − RM300 = RM200. Watch out: the box comes after the minus sign, so subtract; adding gives a number bigger than RM9 000.