Arif berjalan 0.4 km ke kedai buku, kemudian 0.3 km lagi ke taman. Berapakah jumlah jarak yang dia jalan? 0.4 km + 0.3 km = ?
tambah perpuluhan = 小数加法
小数加法和整数加法的想法一样:把同一个位上的数加起来。0.4 是 4 个十分之一,0.3 是 3 个十分之一,合起来是 7 个十分之一,也就是 0.7。所以 Arif 一共走了 0.7 km。
例子:0.2 kg + 0.6 kg = 0.8 kg。
注意:答案要写上单位 km,不要只写数字。
tambah perpuluhan = add decimals
Adding decimals works like adding whole numbers: add the digits that are in the same place. 0.4 is 4 tenths and 0.3 is 3 tenths, so together they make 7 tenths, which is 0.7. Arif walked 0.7 km altogether.
Example: 0.2 kg + 0.6 kg = 0.8 kg.
Watch out: write the unit km in your answer, not only the number.
petak = box, persepuluh = tenth
The strip is cut into 10 equal boxes, and each box is 0.1. Colour 4 boxes blue for 0.4, then colour 3 more boxes orange for 0.3. Count all the coloured boxes: 7 boxes make 0.7.
Example: colour 2 boxes, then 6 more → 0.2 + 0.6 = 0.8.
Watch out: start the second colour where the first colour stops, not from the first box again.
titik perpuluhan = decimal point, lajur = column
In the place value table, line up the decimal points in one column so ones sit under ones and tenths sit under tenths. Start adding from the tenths on the right: 4 + 3 = 7. Then the ones: 0 + 0 = 0. The answer is 0.7.
Example: 0.1 + 0.8 → tenths 1 + 8 = 9 → 0.9.
Watch out: the decimal point in the answer goes in the same column as the others.
Cuba kira
Puan Rosnah membeli 0.2 kg cili dan 0.5 kg bawang. Berapakah jumlah jisimnya?
jumlah = 总和;jisim = 质量
“jumlah”表示要把两样东西合起来,所以用加法。0.2 是 2 个十分之一,0.5 是 5 个十分之一,合起来是几个十分之一?想一想,再写成小数,别忘了单位 kg。
例子:0.4 kg + 0.4 kg = 0.8 kg。
注意:十分之一加十分之一,答案还是十分之一,不会变成百分之一。
jumlah = total, jisim = mass
The word jumlah tells you to put the two masses together, so you add. 0.2 is 2 tenths and 0.5 is 5 tenths. How many tenths is that altogether? Write it as a decimal with the unit kg.
Example: 0.4 kg + 0.4 kg = 0.8 kg.
Watch out: tenths plus tenths gives tenths, never hundredths.
petak seratus = hundred grid, perseratus = hundredth
In the hundred grid each small square is 0.01 and each row (baris) of 10 squares is 0.1. Shade 32 squares blue for 0.32. Since 0.5 = 0.50, shade 50 more squares orange. Altogether 82 squares are shaded, so the mixture has a mass of 0.82 kg.
Example: shade 15, then 60 more → 0.15 + 0.6 = 0.75.
Watch out: 0.5 means 50 small squares, not 5 squares.
tambah sifar = add a zero
When the two decimals have different numbers of digits, write 0.5 as 0.50; a zero at the end does not change its value. Line up the decimal points, then add: hundredths 2 + 0 = 2, tenths 3 + 5 = 8, ones 0. The answer is 0.82.
Example: 0.6 + 0.13 → 0.60 + 0.13 = 0.73.
Watch out: putting the 5 under the hundredths gives the wrong answer 0.37.
susun digit = arrange the digits
One number has one decimal place and the other has two. Write 0.6 as 0.60 first, then stack the numbers so the decimal points are in one column. Add from the hundredths, and check where the decimal point goes in the answer.
Example: 0.3 + 0.45 → 0.30 + 0.45 = 0.75.
Watch out: lining up the 6 under the 1 of 0.21 means the points are not lined up.
garis nombor = number line, lompat = jump
Start at 0.27 on the number line. Split 0.48 into four jumps of 0.10 and one jump of 0.08. The 0.10 jumps land on 0.37, 0.47, 0.57 and 0.67, and the last jump of 0.08 lands on 0.75.
Example: 0.14 + 0.32 → three jumps of 0.10 reach 0.44, then 0.02 more → 0.46.
Watch out: each jump of 0.10 adds 1 to the tenths digit only.
kumpul semula = regroup
Now use the column method for 0.27 + 0.48. Hundredths: 7 + 8 = 15. Fifteen hundredths are 1 tenth and 5 hundredths, so write 5 and carry 1 to the tenths. Tenths: 2 + 4 + 1 = 7. The answer 0.75 matches the number line.
Example: 0.19 + 0.36 → 9 + 6 = 15, write 5, carry 1 → 0.55.
Watch out: the carried 1 is one tenth, so add it in the tenths column.
padankan = match
For each card, check whether the numbers have one or two decimal places, and add a zero if they differ. Line up the points and add; if the hundredths make 10 or more, carry 1 to the tenths. Then find the matching answer card.
Example: 0.25 + 0.5 → 0.25 + 0.50 = 0.75.
Watch out: 0.4 + 0.05 is not 0.09, because the 4 is in the tenths and the 5 is in the hundredths.
anu = unknown, tolak = subtract
In 0.15 + □ = 0.62, the box is the missing part. The bar model shows the whole is 0.62 and one part is 0.15, so the other part is 0.62 − 0.15. In the hundredths, 2 is less than 5, so regroup: 12 − 5 = 7, then 5 − 1 = 4.
Example: 0.3 + □ = 0.9 → 0.9 − 0.3 = 0.6.
Watch out: to find a missing part, never add the two numbers.
Cari anu
0.5 + □ = 0.93
cari nombor yang hilang = 找出缺少的数
加法算式缺了一个加数,就用总数减去已知的加数。这里要先把 0.5 写成 0.50 再对齐小数点。算完后把答案加回 0.5,检查是不是 0.93。
例子:0.2 + □ = 0.68 → 0.68 − 0.20 = 0.48。
注意:把 0.5 当成 0.05 来减,就是小数点没对齐。
cari nombor yang hilang = find the missing number
When one addend is missing, subtract the known addend from the total. Here the total is 0.93 and the known addend is 0.5, which you should write as 0.50 before lining up the points. Afterwards, add your answer to 0.5 to see if you get 0.93.
Example: 0.2 + □ = 0.68 → 0.68 − 0.20 = 0.48.
Watch out: taking away 0.05 instead of 0.50 means the points were not lined up.
digit yang hilang = missing digits
Two digits of the second addend are hidden. Find them by subtracting the first addend from the sum: 0.80 − 0.36. In the hundredths, 0 is less than 6, so regroup 1 tenth first, then subtract place by place. Fill in the boxes and add again to check.
Example: 0.25 + 0.□□ = 0.70 → 0.70 − 0.25 = 0.45.
Watch out: 0 − 6 cannot be turned around into 6 − 0.
Ringkasan
Syabas!
Titik perpuluhan selajur
Susun titik perpuluhan dalam satu lajur, tulis sifar jika perlu, kemudian tambah seperti nombor bulat. Kumpul semula apabila perseratus mencapai 10.