Page 51 - Math E. Booklet prim 4 (first term 2025)_Neat

Complex shapes

We can calculate the area and perimeter of odd shapes by

several ways. 5 cm
Example (1)

Calculate the perimeter and the area of 13 cm

the opposite figure. 7 cm

Answer 15 cm
First: Perimeter

To calculate perimeter , divide the rectangle into rectangles to

find the known side then, perimeter of the opposite figure 5 cm
13 cm
is = 5 + 6 + 10 + 7 + 15 + 13 = 46 cm 6 cm
Second: Area 10 cm

7 cm

Area of blue rectangle = 6 × 5 = 30 cm2 15 cm
Area of green rectangle = 7 × 15 = 105 cm2
Total area = 105 + 30 = 135 cm2

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