Grade
4

Which One Doesn't Belong? Hidden Math

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: 148 + or minus 1-splat-7 = 335. B: splat-1-0 + or minus 4-splat-5 = 325. C: 4-1-splat minus splat-9 = splat-3-5. D: splat-splat-7 + or minus 552 = 335.
Hint: What number could be hidden under each splat? 

Challenge

Find reasons why each of the equations might not belong with the other three.

Share

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

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Reference for Educators

Sample problems and solutions