الأسبوع 16 · المحور الثالث «المواطنة الرقمية»، الدرس ١ «المستكشف النشط»: جمع بيانات البيئة ونشر المعلومات الصحيحة · 3 دروس
2
Reading a pie chart of litter
ICT P5 Term 2, Theme 3: pp. 8–13
GoalRead a pie chart and a bar graph of litter and say what the data tells us.
New words
pie chart · a circle cut into slices; each slice is a share of the wholepercent · a number out of 100; 40 percent means 40 out of every 100total · all the parts added togetheranalyse · to look closely at data to find what it tells us
Explanation
Suppose a school finds 100 pieces of litter in one week. A pie chart shows the whole circle as all 100 pieces, and each slice is one kind of litter. A bigger slice means more pieces. The numbers on the slices are percent, which means out of 100, so they always add up to 100. A bar graph shows the same data with bars: a taller bar means more. Both ways make it easy to see which kind is the biggest problem. Why is it good when many people upload records? More records from more places and days give a more trustworthy picture. When we analyse the picture, we know what to reduce first and where to put bins.
Worked examples
In the pie chart, plastic is 40 percent. Out of 100 pieces, that is 40 pieces. Paper is 25 percent, so 25 pieces. Plastic is the biggest slice.
Check the total: 40 + 25 + 15 + 10 + 10 = 100. If the numbers on a pie chart do not add up to 100, something is wrong and we should count again.
Karim’s class counts litter in its own yard: 12 plastic, 8 paper and 4 metal. The bar graph shows plastic as the tallest bar. Plastic is 4 more than paper (12 − 8 = 4).
Class activity
Make your own litter pie by hand. Imagine 20 pieces: 10 paper, 5 plastic, 5 metal. Draw a circle. Paper is half the circle, so draw a line through the middle. Cut one half again to make two quarters for plastic and metal. Colour the slices and write the number of pieces on each. Then write two sentences that say what your chart tells us and one idea for what the school could do.
Practice
1
What does a bigger slice of a pie chart mean?
More pieces of that kind.
2
A pie chart shows glass 10 percent out of 100 pieces. How many pieces of glass?
10 pieces.
3
Why do the percent numbers on a pie chart add up to 100?
Because the whole circle is all 100 out of 100.
4
Why is it good when many people upload records?
More places and days make the picture more trustworthy.
