sstrike's answer to O help's Primary 5 Maths Area & Volume Singapore question.

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sstrike
Sstrike's answer
5567 answers (A Helpful Person)
1st
Question itself is not complicated
The way shown here only prove that the question number is wrong

Answer of the quadrilateral shape
= ½ square + given triangle
= ¹¹⁄₂₀ of big square

This is within P5 syllabus.