Unit 21
Cabar Minda
Kad digit:
9
1
7
Susun kad untuk membentuk nombor yang dibahagi.
求被除数 = cari nombor yang dibahagi
知道商和余数，就可以反过来求被除数：被除数 = 除数 × 商 + 余数。先用乘法算出 4 × 179，再加上余数 3，就知道三张卡要怎样排。
例子：□ ÷ 3 = 20 baki 1 → 3 × 20 + 1 = 61。
注意：余数也要加进去，不能漏。
find the number divided = cari nombor yang dibahagi
If you know the answer and the remainder, you can work backwards: number divided = divisor × answer + remainder. Work out 4 × 179, add the remainder 3, and you will know how to arrange the three cards.
Example: □ ÷ 3 = 20 baki 1 → 3 × 20 + 1 = 61.
Watch out: remember to add the remainder too.
Langkah 1
Berapakah 4 × 179?
先乘 = darab dahulu
4 × 179：个位 4×9=36，写 6 进 3；十位 4×7=28，+3 = 31，写 1 进 3；百位 4×1=4，+3 = 7。积是 716。这一步先把商乘回除数，下一步再加上余数。
例子：3 × 125 = 375。
注意：进位的数字要加上去。
multiply first = darab dahulu
4 × 179: ones 4×9=36, write 6 carry 3; tens 4×7=28, +3 = 31, write 1 carry 3; hundreds 4×1=4, +3 = 7. The product is 716.
Example: 3 × 125 = 375.
Watch out: add the carried digits.
Langkah 2
716 + 3 = ▢▢▢
加上余数 = tambah baki
716 + 3 = 719，所以被除数是 719，三张卡按 7、1、9 的次序排。检查：719 ÷ 4 = 179 baki 3 ✔（4 × 179 = 716，719 − 716 = 3）。
例子：2 × 45 + 1 = 91 → 91 ÷ 2 = 45 baki 1。
注意：点卡片的次序就是百、十、个。
add the remainder = tambah baki
716 + 3 = 719, so the number divided is 719; arrange the cards 7, 1, 9. Check: 719 ÷ 4 = 179 baki 3 ✔ (4 × 179 = 716, 719 − 716 = 3).
Example: 2 × 45 + 1 = 91 → 91 ÷ 2 = 45 baki 1.
Watch out: tap the cards in the order hundreds, tens, ones.
Teka-teki 2
Nombor apakah jika dibahagi 6, hasilnya 45 baki 4?
反过来算 = kira secara songsang
被除数 = 6 × 45 + 4。6 × 45 = 270，270 + 4 = 274。检查：274 ÷ 6 = 45 baki 4 ✔。270 忘了加余数；266 是减了余数。
例子：5 × 30 + 2 = 152 → 152 ÷ 5 = 30 baki 2。
注意：余数是“加”上去，不是减。
work backwards = kira secara songsang
Number divided = 6 × 45 + 4. 6 × 45 = 270 and 270 + 4 = 274. Check: 274 ÷ 6 = 45 baki 4 ✔. 270 forgets the remainder; 266 subtracts it.
Example: 5 × 30 + 2 = 152 → 152 ÷ 5 = 30 baki 2.
Watch out: the remainder is added, not subtracted.
Teka-teki 3
Apabila sesuatu nombor dibahagi dengan 9, apakah baki terbesar yang mungkin?
最大的余数 = baki terbesar
余数一定要比除数小。除以 9 的时候，余数可以是 0 到 8，所以最大的余数是 8。如果剩下 9 个，就可以再多分一组。
例子：除以 4，最大余数是 3。
注意：余数等于除数就不对了。
greatest remainder = baki terbesar
The remainder must be smaller than the divisor. Dividing by 9, the remainder can be 0 to 8, so the greatest is 8. If 9 were left, one more group could be made.
Example: dividing by 4, the greatest remainder is 3.
Watch out: a remainder equal to the divisor is not allowed.
Ringkasan