Which One Doesn't Belong? Fractions & Models

Look at this set of four pictures. Decide which one doesn’t belong with the other three. Use math words to describe your thinking. There are many ways to think about each one!

A: 2 and 1-fifth minus 3-fourths = d. B: A clock model shows one face 3-fourths shaded + one face 2-thirds shaded. 3-fourths plus 2-thirds = t. C: A number line model shows a jump from 7-eighths to 1 and 5-eighths.7-eighths + question mark = 1 and 5-eighths. D: A money model shows 1 quarter + m = 2 dollar bills and 4 dimes. 1-fourth + m = 2 and 4-tenths.


See if you can find reasons why each of the pictures might not belong with the other three.


Explain your thinking to someone else. Do they have different reasons why one doesn't belong?