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You can read posting Sarin learns Perimeter, Area and Volume in school(Math Concept) to learn the concept of perimeter and area.
Read also the posting on Sarin learns Shapes and Solids in school (Math Concept) to know about shapes.
Read the posting on Sarin learns the concept of Fraction (mathematics concept) to understand the concept of Fraction.
Challenge yourself with the question before look out for the given solution‼!
Upper primary school mathematics question UPQ415
The diagram is not drawn to scale. ABCD is a square and arc BD is a quarter with centre point at C. What is the fraction of the area of the yellow region in the figure ABCD? If AB = 20 cm, calculate the area of the yellow region (Take π = 3.14)
Figure ABCD is a square
AB = DC = 20 cm
AC bisect the square to two identical isocelete triangles
∠ DAG = ∠ FEC = ∠ FCE = 450
AD = DC and EF = FC
DG = GC and ∠ GDC = ∠ ECF
Arc BD is a quarter with centre point at C
EC = DC = AB
Triangle DGC is identical to triangle EFC
Fit triangle EFC to the position of triangle DGC as below diagram shown
The fraction of the yellow region is ¼ of the figure ABCD.
The area of the figure ABCD = 20 × 20 = 400 cm2
The area of the yellow region = 400 ÷ 4 = 100 cm2
Please note that the solution also shown that the area of a square X is half the area of a square Y, if the diagonal length of square X is equal to the side length of square Y.