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竖式加法 = tambah bentuk lazim 把两个数按数位对齐，从个位开始一列一列往左加。每一列满 10，写个位数，向左进 1；下一列一定要加上这个 1。 例子：40 518 + 2 694 → 个位 8+4=12 写 2 进 1，十位 1+9+1=11 写 1 进 1，百位 5+6+1=12 写 2 进 1，千位 0+2+1=3，万位 4 → 43 212。 注意：连续进位时，每一列都要加上进上来的 1；万位没有加数时，只抄下原来的数字。

column addition = tambah bentuk lazim Line the two numbers up by place value and add column by column from the ones. When a column makes 10 or more, write the ones digit and carry 1 to the next column. Example: 40 518 + 2 694: ones 8 + 4 = 12, tens 1 + 9 + 1 = 11, hundreds 5 + 6 + 1 = 12, thousands 0 + 2 + 1 = 3, ten thousands 4, giving 43 212. Watch out: when carrying in several columns in a row, add the 1 into every next column.

求三个数的和 = jumlahkan tiga nombor “Jumlahkan”就是把几个数全部加起来。三个数按数位对齐，从个位开始一列一列加，每一列的三个数字加上进位；满 10 进 1，满 20 进 2。 例子：10 250 + 5 380 + 4 170 → 个位 0，十位 5+8+7=20 写 0 进 2，百位 2+3+1+2=8，千位 0+5+4=9，万位 1 → 19 800。 注意：一列满二十要进 2；四位数要和五位数的个位对齐。

sum of three numbers = jumlahkan tiga nombor Jumlahkan means add all the numbers. Line up the three numbers and add each column with its carry; carry 1 for 10 or more and 2 for 20 or more. Example: 10 250 + 5 380 + 4 170: ones 0; tens 5 + 8 + 7 = 20, write 0 carry 2; hundreds 2 + 3 + 1 + 2 = 8; thousands 0 + 5 + 4 = 9; ten thousands 1, giving 19 800. Watch out: a column of 20 or more carries 2, and the four-digit number must line up at the ones.

四个数相加 = tambah empat nombor 四个数对齐以后，每一列有四个数字。可以先在一列里找出能凑成 10 的两个数字先加，再加其他数字和进位，这样又快又不容易错。每列满 10 进 1，满 20 进 2。 例子：十位数字 6、4、9、1 → 先 6+4=10，再 9+1=10，这一列一共 20，写 0 进 2。 注意：每一列都要加上右边进上来的数；位数少的数要对齐个位。

adding four numbers = tambah empat nombor With four numbers lined up, each column has four digits. Look for two digits that make 10 and add them first, then the rest and the carry. Carry 1 for 10 or more and 2 for 20 or more. Example: tens digits 6, 4, 9 and 1 make 6 + 4 = 10 and 9 + 1 = 10, so the column is 20; write 0 and carry 2. Watch out: add the carry from the right in every column, and line up shorter numbers at the ones.

用估计检查 = semak dengan anggaran 题目已经给出估计值，要挑出一个合理的准确答案。做法：自己用竖式算出准确的和，再看它是不是和估计值很接近。和估计值差了几千甚至一万的，一定有地方算错。 例子：估计 30 000，准确答案 30 120 合理；如果算出 20 120，就差了一万，不合理。 注意：接近估计值还不够，准确答案也要真的算对；估计不能代替计算。

check with an estimate = semak dengan anggaran The estimate is given; choose the reasonable exact answer. Work out the exact sum in columns and see whether it is close to the estimate. An answer thousands away from the estimate has a mistake. Example: with an estimate of 30 000, an exact answer of 30 120 is reasonable but 20 120 is not. Watch out: being close is not enough; the exact answer must also be worked out correctly.

求第三部分 = cari bahagian ketiga 三所学校的总人数已经知道，A 校和 B 校的人数也知道，问 C 校有多少人。先把已知的两部分加起来，再用总数减去这个和。最后把三部分加起来检查是否等于总数。 例子：总数 10 000，已知两部分是 3 000 和 4 500，3 000 + 4 500 = 7 500，第三部分 = 10 000 − 7 500 = 2 500。 注意：两所学校的人数和只是中间结果，还要做减法；从整千减要连续借位。

find the third part = cari bahagian ketiga The total for three schools is known, and so are schools A and B; how many pupils are in C? Add the two known parts, subtract that sum from the total, then add all three parts to check. Example: a total of 10 000 with parts 3 000 and 4 500: 3 000 + 4 500 = 7 500, so the third part is 2 500. Watch out: the sum of A and B is only a middle step, and subtracting from a whole thousand needs regrouping.

凑成十万 = jumlah 100 000 要从三对数里找出相加刚好等于十万的一对。可以逐对用竖式相加；也可以用快方法：从右边数起，找到最先出现、不是 0 的数位，这一位的两个数字相加要等于 10；它左边的每一位，两个数字相加都要等于 9（因为有进位）；它右边的 0 位加起来还是 0。 例子：72 400 + 27 600：个位、十位都是 0，百位 4 + 6 = 10，千位 2 + 7 = 9，万位 7 + 2 = 9 → 100 000。 注意：每一对都要检查每一位，只看前几位会看错。

make one hundred thousand = jumlah 100 000 Find the pair that adds up to exactly 100 000. Add each pair in columns, or use a shortcut: from the right, find the first place that is not 0 in both numbers; there the two digits must add to 10, every place to its left must add to 9 because of the carries, and the zero places stay 0. Example: 72 400 + 27 600: the ones and tens are 0, hundreds 4 + 6 = 10, thousands 2 + 7 = 9, ten thousands 7 + 2 = 9, giving 100 000. Watch out: check every place of each pair; looking only at the first digits can mislead you.

选三个数凑总数 = pilih tiga nombor untuk jumlah 表格里有五个公园的访客人数，要找出哪三个公园加起来刚好等于指定的总数。可以先估计：把每个数取整到千，把每个选项的三个数大约加一加，离总数太远的先放一边；再把最接近的选项用竖式按数位对齐算出准确的和，和总数比较。 例子：从 1 200、2 450、3 300、1 850 中选三个数凑成 6 950：估计 1 000 + 3 000 + 2 000 = 6 000 较远；1 000 + 2 000 + 3 000 也约 6 000，要细算：1 200 + 2 450 + 3 300 = 6 950 刚好符合。 注意：估计只能帮你先筛选，最后一定要算出准确的和来确认。

choose three to make the total = pilih tiga nombor untuk jumlah The table shows visitors at five parks; which three parks add up to the given total? Estimate first by rounding each number to the nearest thousand and set aside options that are far from the total. Then add the closest option exactly in columns and compare. Example: to make 6 950 from 1 200, 2 450, 3 300 and 1 850, both 1 200, 3 300, 1 850 and 1 200, 2 450, 3 300 estimate near 6 000, so add exactly: 1 200 + 2 450 + 3 300 = 6 950 fits. Watch out: an estimate only helps you sort; always work out the exact sum to confirm.