Idea 9of 22Builds onFinding the number halfwayPut decimals in order by place value
A decimal median can land on hundredths
What is halfway between 12.0 and 12.4?
Today you'll discover
- the median of an even count of decimals
- why it can need hundredths
Think firstFour runners' 60 m times, in seconds
What is the median race time?
Decide first, then press Next. Find the middle pair, then the mark between them.
A row of four race times, 12.4, 11.8, 13.1 and 12.0 seconds, slides into order: 11.8, 12.0, 12.4, 13.1. A short number line from 12.0 to 12.4 marks 12.2 halfway. The last step shows six days of rain in millimetres.
See the whole ideathe big idea and the key word, in one place
The big idea
Halfway between two tenths can need hundredths: between 3.0 and 3.5 is 3.25.
Why hundredths3.0 and 3.5 are 5 tenths apart. Half of 5 tenths is 2.5 tenths, which is 25 hundredths: 3.25.
Easy to get wrongKeep the decimal points lined up when you add: 12.0 + 12.4 = 24.4, then 24.4 ÷ 2 = 12.2.
Key word
- hundredth
- one of 100 equal parts of one whole; 0.25 is 25 hundredths
Ready to use it?
- Find the median of decimal measurements.