Unit 15
Akal Pintar
Dua barang antik dipamerkan di sudut sejarah sekolah.
Gong tembaga
163 tahun
163 tahun
Tempayan tanah liat
76 tahun
76 tahun
年龄差 = beza usia
要先求两件古物相差多少年，用大的年龄减小的年龄；再把相差的年数换成 dekad 和年。两步都要做。
例子：60 年和 45 年相差 15 年 = 1 dekad 5 年。
注意：答案要用题目要求的单位。
difference in age = beza usia
First find how many years apart the two antiques are by subtracting the smaller age from the bigger one, then change that number of years into dekad and years. Both steps are needed.
Example: 60 and 45 years differ by 15 years = 1 dekad 5 years.
Watch out: give the answer in the unit the question asks for.
Cara
Tolak, kemudian tukar unit
163 tahun − 76 tahun
| 0 | 15 | 13 | |
| 1 | 6 | 3 | |
| − | 7 | 6 | |
| 8 | 7 |
87 tahun = 8 dekad 7 tahun
先减再换 = tolak, kemudian tukar
一百六十三减七十六：个位三不够减六，借位得十三减六等于七；十位借走一变五，不够减七，再向百位借，十五减七等于八，得八十七年。八十七年里有八个十年，剩七年，所以是八个 dekad 七年。
例子：100 年 − 72 年 = 28 年 = 2 dekad 8 年。
注意：减完以后，还要把年换成 dekad 和年。
subtract, then change = tolak, kemudian tukar
163 − 76: 3 is less than 6, so borrow: 13 − 6 = 7; the tens become 5, less than 7, so borrow again: 15 − 7 = 8, giving 87 years. 87 years hold eight 10s with 7 left: 8 dekad 7 years.
Example: 100 − 72 = 28 years = 2 dekad 8 years.
Watch out: after subtracting, you still need to change the years into dekad and years.
Semak
Gong itu lebih tua daripada tempayan sebanyak …
相差多少 = berapa lebih tua
“老多少”是在问两个年龄相差多少，要用大的年龄减小的年龄，不是相加。用竖式减的时候，每一位不够减就向前一位借一，借位后前一位要少一。减出年数以后，再把年数分成几个十年和剩下的年。
例子：92 年 − 47 年 = 45 年 = 4 dekad 5 年。
注意：连续借位时最容易忘记前一位已经少了一。
how much older = berapa lebih tua
How much older asks for the difference between the two ages, so subtract the smaller age from the bigger one; do not add. In column subtraction, borrow from the next place whenever a digit is too small, and that place becomes 1 less. Then split the years into tens and the years left.
Example: 92 − 47 = 45 years = 4 dekad 5 years.
Watch out: with two borrows in a row it is easy to forget that a place has already gone down by 1.
Ringkasan