Idea 8of 22Builds onUnlikely, even chance, likely
Put a probability on the line
Where does a fraction like 3/8 go on the probability line?
Today you'll discover
- how to cut the line into equal steps
- how to use 0, 1/2 and 1
- how to place any fraction
Think firstThe probability of orange is 3/8
The probability of orange is 3/8. Which part of the line does it go in?
Decide first, then press Next. Compare the fraction with 1/2 first.
A line from 0 to 1 with impossible, unlikely, even chance, likely and certain. The line is cut into eighths, labelled 1/8 to 7/8; a pointer for orange lands at 3/8, one step left of the middle. The last step shows a line cut in thirds for a rain forecast of 2/3.
See the whole ideathe big idea and the key word, in one place
The big idea
Compare a probability with the benchmarks 0, 1/2 and 1 to see where it goes.
EighthsCut the line into 8 equal steps. 3/8 is 3 steps from 0; 1/2 is 4 steps; 7/8 is 7 steps, near certain.
Easy to get wrongBig numbers do not make a big fraction. 3/8 is less than 1/2, even though 3 and 8 are more than 1 and 2.
Key word
- benchmark
- a known point you compare with, like 0, 1/2 or 1 on the probability line
Ready to use it?
- Place a probability on a probability line.
- Use 1/2 to say whether an event is likely or unlikely.