Given ∠BOC = 45°

∠AOC = 180° – 45° = 135°

Area of circle = πr^{2}

Area of region X = θ/360°x πr^{2}

= 135/360 x πr^{2} = 3/8 x πr^{2}

Probability that the spinner will land in the region

X = (Area of region of x)/(total area of circle) = (3/8 x πr^{2})/πr^{2} = 3/8