# Sarin learns Shapes and Solids in school part 57 (Math Question)

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The blog postings are about the Singapore Math. The readers can learn from the postings on 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 learn the skills to deal 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 Angles and Shapes.

Read the posting on Sarin learns Lines and Angles (Math concept) to understand the concept of lines and angles.

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

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

Upper primary school mathematics question UPQ491

The figure below is not drawn to scale. CDE is a straight line. Find ∠ CAD.

Solution:

BCD is a triangle and ∠ ABD is exterior angle of triangle BCD

∠BCD = 700 – 330 = 370

ACD is a triangle and ∠ADE is exterior angle of triangle ACD

∠ CAD = 1210 – 370 = 840

Or,

CDE is a striaght line,

∠ADB = 1800 – 1210 – 330 = 260

ABD is a triangle

∠CAD = 1800 – 700 – 260 = 840

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