# Sarin learns Perimeter, Area and Volume in school part 100 (Math Question)

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The blog postings are about the Singapore Math. The readers can learn from the postings about Solving Singapore Primary School Mathematics. The blog presents the Math Concept, the Math Questions with solutions that teaches in Singapore Primary Schools. You or the kids can acquire the skill of dealing with the Math Modeling, the Math Problem Solving and the Problem Sum from Lower Primary School to Upper Primary School level after reading the blog postings. This posting is an upper primary school math question on Shapes and Area.

You can read posting Sarin learns Perimeter, Area and Volume in school(Math Concept) to learn the concept of area.

Read also the posting on Sarin learns Shapes and Solids in school (Math Concept) to know about shapes.

Challenge yourself with the question before look out for the given solution‼!

Upper primary school mathematics question UPQ457

ABCD is a square with a semi-circle of diameter 8 cm, cut from the side CD as shown. What is the area of the blue portion in terms of π?

Solution:

ABCD is a square

AB = BC = CD = AD = 8 cm

The area of the semi-circle = 1/2 x π × r × r = 1/2 x π × 4 × 4 = 8π cm2

The area of the square = 8 × 8 = 64 cm2

The area of the blue portion = (64 – 8π) cm2