KS1 KS2 Perimeter of 2D shapes missing number reasoning geometry worksheet

A short, simple, differentiated worksheet for year 2, year 3, year 4, year 5 and year 6.
Students look at known lengths sides of 2D shapes, and their perimeter, and work out the length of a missing side. Includes mainly simple 2D shapes: triangles, quadrilaterals, and composite rectilinear shapes.

Includes an easier challenge (low, simple numbers), a middle challenge (higher numbers), and a more difficult challenge (numbers in the hundreds and thousands).

Would work well as a homework, or a worksheet for a lesson on reasoning and perimeter.