When introducing the problem to Year 5 (Oak) we discussed that numerically equal would not be the same measurement and the difference between area and perimeter.
Now children worked in pairs to talk through their ideas of solving the problem and the option of using squared paper to try out the problem.
It was interesting to listen to how the pairs were working on the problem. Most pairs used squared paper. Some drew a variety of squares chosen randomly until they reached an answer. Some were more systematic and drew squares and calculated area/perimeter until they found one that worked-See pictures: