The relation is that two 1/4 pieces equal one 1/2 piece. So, 1/2 = 2/4. Both show the same amount of the whole, but they are written using different numbers. They are called equivalent fractions.
Class 5 Mathematics Maths-Mela Chapter 2 Fractions question answer
Class 5 NCERT Maths-Mela Chapter 2 Fractions solution
When I use the kit, I see that one piece of half is exactly the same as two pieces of one-fourth. That means if I join two 1/4 pieces, they completely cover a 1/2 piece. So, 1/2 and 2/4 represent the same quantity. This shows the relation: 1/2 = 2/4. They are different names, but they mean the same part of a whole.
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