Grade
4

Which One Doesn’t Belong? Different Dimensions

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. shows a rectangle made of base ten pieces. 2 100-grids side by side. 3 ten-strips (1 on the side, 2 along the bottom), and 1 unit (at the bottom right corner). B. shows an irregular shape made with 2 rectangles. One is 20 by 11. The other is 11 by 1. C. shows 2 100-grids side by side. Along the bottom edge are 1 ten-strip and 4 units in a 2 by 2 square. D. shows 2 100-grids side by side. Along the bottom edge of the left 100-grid are 3 ten strips (horizontal). 1 unit is to the right of the first 10-strip.

Challenge

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

Share

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

Printable Version

Google doc for printing and copying

Seesaw Version

Activity for the Seesaw platform

Reference for Educators

Sample problems and solutions