Question 82
Find the area of shaded portion.
Area of shaded portion=Area of trapezium ABCH+Area of trapezium CDEF + Area of rectangle GHCF
Area of trapezium = 12×(Sum of parallel sides)×(Height)
∴Area of trapezium ABCH
=12×([12−3]+6)×4
=12×9×4
=9×2
=18 cm2
∴Area of trapezium CDEF
=12×(8+[16−4])×3
=12×(8+12)×3
=12×20×3
=10×3
=30 cm2
∴Area of rectangle GHCF
=4× 3
=12 cm2
Hence, area of shaded portion
=(18+30+12) cm2
=60 cm2