Question

Find the area of the surface of the octagonal nut....

Answer 1

$area \: of \: octagon = 2 \times area \: of \: trapezium + area \: of \: rectangle \\ = 2 \times (1 \div 2 \times 4 \times( 5 + 11) )+ (5 \times 11) \\ = 2×32 + 55 \\ = 64 + 55 \\ = 119$