What you’ll learn
Understand ratio relationships.
Key idea
A ratio compares counts in the stated order; unequal counts are allowed.
Reversing counts changes the named ratio; equal counts are not required.
Worked example
Classify examples and non-examples for the concept 'Understand ratio relationships'.
A bag has 2 red tiles and 18 blue tiles. Is 18:2 an example of the red-to-blue ratio? Classify with order evidence.
- The named order fixes the first color as red and the second as blue.
- The counts give 2:18; the proposed 18:2 reverses that order.
Answer: Non-example — red-to-blue requires 2 red before 18 blue, so the ordered ratio is 2:18.
Quick Check
Classify examples and non-examples for the concept 'Understand ratio relationships'.
A bag has 4 red tiles and 5 blue tiles. Is 4:5 an example of the red-to-blue ratio? Classify with order evidence.