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最小的五位数 = nombor lima digit paling kecil 题目问最小的五位数。想一想：五位数有五个数位，最左边的万位不能是 0，所以万位最小只能放哪个数字？其他四个数位又可以放最小的哪个数字？把它们写出来就是最小的五位数。也可以想：最大的四位数再加 1，会变成什么？ 例子：最小的三位数是 100，最大的两位数 99 加 1 就是它。 注意：最大的数和最小的数不要弄反；数一数写出来的数是不是刚好五位。

smallest five-digit number = nombor lima digit paling kecil What is the smallest five-digit number? The first place cannot be 0, so which is the smallest digit allowed there? What is the smallest digit for the other four places? You can also ask what the largest four-digit number becomes when you add 1. Example: the smallest three-digit number is 100, which is the largest two-digit number 99 plus 1. Watch out: do not mix up largest and smallest, and count that your number has exactly five digits.

至少补到一万 = sekurang-kurangnya 10 000 题目要找一个四位数，加上已知的数以后和是五位数，也就是和至少 10 000。先用 10 000 减去已知的数，算出“至少要多少”；再看哪个选项等于或大于这个数。 例子：2 800 + □ 要成为五位数，10 000 − 2 800 = 7 200，所以 □ 至少要 7 200，例如 7 250 可以，7 150 不行。 注意：差一点点也不行，比最少的数小，和就只有四位。

at least ten thousand = sekurang-kurangnya 10 000 Find the four-digit number that makes the sum a five-digit number, so the sum must be at least 10 000. Work out 10 000 minus the given number to find the least amount needed, then choose the option that is equal or bigger. Example: for 2 800 + □ to have five digits, 10 000 − 2 800 = 7 200, so 7 250 works and 7 150 does not. Watch out: even a little short is not enough; below the least amount the sum has only four digits.

最大的和 = jumlah paling besar 题目问两个四位数相加，和最大可以是多少。要让和最大，两个加数都要尽量大，所以先想：最大的四位数是多少？再把两个最大的四位数相加，用竖式算，注意每一位都要进位。 例子：两个最大的三位数相加：999 + 999 = 1 998。 注意：结果一定是两个四位数的和，不能大过两个最大的四位数相加；只有一个五位数本身不是“和”。

the largest sum = jumlah paling besar What is the biggest possible sum of two four-digit numbers? Both numbers must be as big as possible, so first find the largest four-digit number, then add it to itself in columns, regrouping in every place. Example: the two largest three-digit numbers give 999 + 999 = 1 998. Watch out: the answer must be a sum of two four-digit numbers, so it cannot be more than the two largest ones added.