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进位时减 1 = kurang 1 apabila dibundarkan ke atas 题目给出取整到千的结果，要推出原来的千位。先看百位：百位 5 到 9 会进位，表示结果的千位比原来多 1，所以原来的千位要比结果少 1；百位 0 到 4 就不变。最后把数字代回去检查。 例子：2□ 700 取整到千是 29 000：百位 7 进位，所以 □ = 9 − 1 = 8；检查 28 700 → 29 000。 注意：不要直接抄结果里的千位数字，先想清楚有没有进位。

subtract 1 when it rounds up = kurang 1 apabila dibundarkan ke atas The rounded result to the nearest thousand is given; find the thousands digit before rounding. If the hundreds digit is 5 to 9 the number rounded up, so the thousands digit before rounding is one less than the result; with 0 to 4 it is the same. Then check. Example: if 2□ 700 rounds to 29 000, the 7 hundreds round up, so □ = 9 − 1 = 8; check 28 700 → 29 000. Watch out: do not just copy the thousands digit of the result; first decide whether it rounded up.

最大可能的数字 = digit paling besar yang mungkin 题目说取整到万以后，万位没有改变，要找千位“最大”可能是几。先想：取整到万看千位；万位没变，表示没有进位。把 0 到 9 逐个想一想，哪些数字放在千位不会进位？把这些可以的数字列出来，再挑出最大的一个。 例子：□ 是一个数字，要让 □ + 6 小于 10，可以的数字是 0、1、2、3，其中最大是 3。 注意：题目问“最大”，不是随便一个可以的数字；也要记得刚好是 5 时会进位。

the largest possible digit = digit paling besar yang mungkin After rounding to the nearest ten thousand the ten thousands digit did not change, so there was no rounding up. Which thousands digits from 0 to 9 do not round up? List them, then pick the largest. Example: if □ + 6 must be less than 10, the allowed digits are 0, 1, 2 and 3, and the largest is 3. Watch out: the question asks for the largest allowed digit, and remember that exactly 5 rounds up.

正好在中间也进位 = tepat di tengah dibundarkan ke atas 题目给出取整到千的结果，原数的百位刚好是 5。规则是：刚好在中间时取较大的整千，也就是要进位。所以原来的千位比结果的千位少 1。推出来以后代回去检查。 例子：3□ 500 取整到千是 37 000：百位 5 进位，所以 □ = 7 − 1 = 6；检查 36 500 → 37 000。 注意：百位是 5 时要进位，不是不变；这是最容易出错的地方。

exactly halfway rounds up = tepat di tengah dibundarkan ke atas The result to the nearest thousand is given and the hundreds digit is exactly 5. The rule says halfway goes to the bigger thousand, so it rounds up and the thousands digit before rounding is one less than the result. Then check. Example: if 3□ 500 rounds to 37 000, the 5 hundreds round up, so □ = 7 − 1 = 6; check 36 500 → 37 000. Watch out: a hundreds digit of 5 rounds up; treating it as stay the same is the most common mistake.