Kelas 3 Cerdik mahu memilih jus untuk hari sukan. Mereka bertanya kepada kawan-kawan: jus apakah yang kamu suka? Bagaimanakah mereka mengumpul, mengelas dan menyusun jawapan itu?
data = data; collect = kumpul; classify = kelas; organise = susun
This unit is about handling data. Class 3 Cerdik must choose juice for sports day, so they ask friends which juice they like. Every answer is one piece of data. We will collect the answers, sort them into kinds, and arrange them in a table so the favourite is easy to spot.
Example: asking 16 friends gives 16 answers such as orange or apple, and together they form one set of data.
Watch out: each friend is counted once; asking the same person twice makes the numbers too big.
observing = memerhati; questionnaire = soal selidik; interview = temu bual
There are three common ways to collect data. Observing means watching and writing down each thing you see, such as the colours of cars passing the school gate. A questionnaire is a form that friends fill in by ticking a choice. An interview means asking friends one by one and writing their answers.
Example: to find out how friends travel to school, hand out a form with walk, bicycle, bus and car, and each friend ticks one.
Watch out: each friend ticks only one choice, or the answers cannot be sorted.
Langkah 2
Mengelas dengan gundal
Pangkah satu data → lukis satu gundal · gundal ke-5 dilukis melintang
tally mark = gundal; cross out = pangkah; a bundle = satu ikat
When sorting, look at one piece of data at a time: take the first car, cross it out, then draw one line in the row for its colour. Going on like this means nothing is missed and nothing is counted twice. The fifth mark is not another upright line; it is drawn across the first four to make a bundle of five. Count in fives: red is one bundle and one line, so 6, and blue has 4 lines.
Example: 13 tally marks are two bundles and three lines, counted 5, 10, 11, 12, 13.
Watch out: the fifth mark must go across, because five upright lines are hard to read at a glance.
reading tally marks = baca gundal
The picture shows two bundles; each bundle has four upright lines and one line across, which makes 5, so two bundles make 10. Two more upright lines follow, and 10 + 2 = 12. The answer is 12. Counting a bundle as only 4 (forgetting the line across) gives 10, and counting each bundle as 10 gives 22.
Example: three bundles and one line make 15 + 1 = 16.
Watch out: the slanted line counts too, so a bundle is always 5.
tick = tanda ✓; count in fives = kira lima-lima
Besides tally marks, we can put one tick for each piece of data. Both ways give the same number: red is 6 and blue is 4 either way. The difference is that a long row of ticks must be counted one by one, which is easy to get wrong, while tally marks come in bundles of five, so we can skip-count 5, 10, 15. With lots of data, tally marks are quicker.
Example: 11 ticks for white need 11 counts, but as tally marks they are two bundles and one line, counted 5, 10, 11.
Watch out: one piece of data gets exactly one tick or one line, never more.
organise in a table = susun dalam jadual; class = kelas; number = bilangan
Above are the 16 raw answers, mixed up and hard to read. To organise them, first list every kind (orange, apple, mango, watermelon), then go through the answers one at a time, crossing each out and drawing one tally mark for its kind, and finally write how many in the Bilangan column. Now orange 7, apple 3, mango 4 and watermelon 2 can be seen at once.
Example: if one more friend says mango, the mango row gets one more line and becomes 5.
Watch out: the numbers in the table must add up to the number of people asked, here 7 + 3 + 4 + 2 = 16.
从原始数据数一种 = kira satu kelas daripada data
这一题的 14 个回答里,要数“Merah”有几个。最稳的方法是从第一个开始,看到 Merah 就在纸上画一根计数字符,一路看到最后,不要跳着看。这样数出 Merah 一共 6 个。选 5 多半是漏看了一个,选 7 多半是有一个数了两次。
例子:同一组数据里,Kuning 有 3 个,Hijau 有 3 个,Biru 有 2 个。
注意:数完后把各种颜色加起来,6 + 3 + 3 + 2 = 14,跟总数一样才对。
counting one class in raw data = kira satu kelas daripada data
Among these 14 answers we must count how many say Merah. The safest way is to start from the first answer and draw a tally mark every time Merah appears, going all the way to the end without skipping. That gives 6 for Merah. Choosing 5 usually means one was missed, and 7 usually means one was counted twice.
Example: in the same data, Kuning appears 3 times, Hijau 3 times and Biru 2 times.
Watch out: add up all the colours afterwards, 6 + 3 + 3 + 2 = 14, which must match the total.
Cuba
Berdasarkan jadual jus, berapakah lebih murid yang suka jus Oren daripada jus Tembikai?
how many more = berapa lebih; difference = beza
Once the table is ready, we can use it to answer questions. How many more means subtraction: orange has 7 and watermelon has 2, and 7 − 2 = 5, so 5 more pupils like orange. 9 comes from adding the two numbers, and 2 is just the watermelon count.
Example: mango is liked by 4 − 3 = 1 more pupil than apple.
Watch out: for how many more, take the smaller number from the bigger one; do not add them.
matching tally marks = padankan gundal
For each group, first count the bundles, each worth 5, then add the single lines after them. One bundle and two lines make 7; one bundle and four lines make 9; two bundles and three lines make 10 + 3 = 13; one bundle alone is 5. Four upright lines with no line across mean only 4, and the fifth stroke turns them into a bundle.
Example: two bundles and one line make 11, and three bundles make exactly 15.
Watch out: a bundle is never 4; the slanted stroke is one piece of data as well.
Langkah 4
Semak jumlah
20 orang murid ditanya tentang sukan kegemaran
Sukan
Gundal
Bilangan
Bola sepak
9
Badminton
7
Renang
5
Jumlah
21 ✗
Murid ditanya: 20 · 9 + 7 + 5 = 21 → ada data dikira dua kali
check = semak; total = jumlah; counted twice = dikira dua kali
A finished table must be checked: add the numbers in every class, and the sum should equal the number of people asked. Here 20 pupils were asked, but 9 + 7 + 5 = 21, one too many, so one answer was counted twice. If the sum is smaller than 20, an answer was missed. When it does not match, count again, crossing out as you go.
Example: 15 people asked and a table of 6, 5 and 3 gives 14, one short, so one answer was missed.
Watch out: do not simply change a number to make it fit; go back to the raw data and recount.
Cuba
Sepatutnya 20 orang murid. Badminton dikira satu kali lebih. Berapakah bilangan Badminton yang betul?
correcting a number = betulkan bilangan
The table above adds up to 21, but there are only 20 pupils. The question says badminton was counted once too often, so its number must go down by 1: 7 − 1 = 6. After fixing it, 9 + 6 + 5 = 20, which matches, so the table is right. 8 adds 1 instead, and 7 leaves the mistake in place.
Example: if swimming had been missed once, its 5 would become 6.
Watch out: after correcting, add the column again to be sure it equals the number of pupils.
Ringkasan
Syabas!
kumpul → kelas (gundal) → susun (jadual) → semak
Kumpul data dengan memerhati, soal selidik atau temu bual. Kelas dengan gundal: gundal ke-5 melintang. Susun dalam jadual. Semak: jumlah mesti sama dengan bilangan data.