The are of a sector of a circle is 308 cm2, with the central angle measuring 45o. The radius of the circle is :

14 cm 21 cm 7 cm 28 cm

28 cm

We know that, Area of a sector = \(\frac{ θ }{360°  }\) × πr2  We have, The area of a sector of a circle = 308 cm2 The angle of the sector = 45° According to the question, \(\frac{ 45°}{360°}\) × πr2  = 308 = πr2 = 308 × 8 = \(\frac{22}{7}\) × r2 = 2464 = r2 = 784 = r = 28cm