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 Fraction, Ratio and Area.

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

Read the posting on **Sarin learns ratio in school (Math Concept)**** **to learn about concept of Ratio.

Read the posting on **Sarin learns the concept of Fraction (mathematics concept) **to understand the concept of Fraction.

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 UPQ489**

EFGH is a rectangle formed using 4 triangles A, B, C and D. The area of Triangle A is 72 cm^{2}. The ratio of area of Triangle C to area of Triangle B is 13 : 10. The area of Triangle D is 6/5 the area of Triangle B. Find the area of rectangle EFGH.

Solution:

Subdivide Rectangle EFGH by two with dotted line,

Area A = Area D1 + Area B1

Area C = Area D2 + Area B2

Area A + Area C = Area D1 + Area D2 + Area B1 + Area B2

Area (A + C) = Area (D + B)

Given,

Area C : Area B = 13 : 10

And

Area D is 6/5 of Area B

Area D : Area B = 6 : 5 = 12 : 10

Area C : Area B : Area D : Area (B + D) = 13 : 10 : 12 : 22

Since Area (A + C) = Area (D + B)

Area A : Area C : Area (A + C) = 9 : 13 : 22

Therefore,

9 units = 72 cm^{2}

1 unit = 8 cm^{2}

The area of rectangle EFGH = 2 × 22 × 8 = 352 cm^{2}