Idea 3of 22Builds onPart to part
Part to whole
How do you compare one part with the whole set?
Today you'll discover
- what the whole is
- how part to whole is also a fraction
- how it differs from part to part
Think first3 orange and 5 blue on one tray
What is the ratio of orange counters to all the counters?
Decide first, then press Next. Add the two colours to find the whole.
3 orange circles and 5 blue squares on a tray. Under it, the lines orange to all equals 3 to 8 and blue to all equals 5 to 8. Then 5 orange and 2 blue, orange to all 5 to 7; then 6 orange and 9 blue, orange to all 6 to 15. The last step shows 3 orange and 12 blue.
See the whole ideathe big idea and the key word, in one place
The big idea
A part-to-whole ratio compares one part with the whole set, like a fraction.
A fraction is part to wholeOrange to all, 3 : 8, says 3 out of 8 counters are orange. As a fraction, that is 3/8 of the tray.
Compare themPart to part: 3 : 5, orange to blue. Part to whole: 3 : 8, orange to every counter. Same tray, different question.
Key word
- part-to-whole ratio
- a ratio that compares one part of a set with the whole set, like orange counters to all the counters
Ready to use it?
- Write a part-to-whole ratio.
- Write a part-to-whole ratio as a fraction.