The blog postings are about the Singapore Math. The readers can learn from the postings on Solving Singapore Primary School Mathematics. You or your kids can learn dealing with Math modeling, Problem Sum from Lower Primary School to Upper Primary School level in Singapore school. This posting is a primary school math question on Triangle and Area.
You can read posting Sarin learns Perimeter, Area and Volume in school(Math Concept) to learn the concept of perimeter, area and volume.
Read also the posting on Sarin learns Shapes and Solids in school (Math Concept) to know about shapes.
Upper primary school mathematics question UPQ190
The figure below is not drawn to scale. Find the area of the coloured region.
The figure is formed by two overlapping triangles with same base length but different height
The area of the coloured region can be determine by substracting the area of the two triangles
The area of the coloured region = ½ × 13 × 21 – ½ × 9 × 13 = 78 cm2
The area can be determine by the different in height of the two triangles
The different in heights = 12 cm
The area of the coloured region = ½ × 13 × 12 = 78 cm2