A spherical mirror is obtained as shown in the figure from a hollow glass sphere, if an object is positioned in front of the mirror, what will be the nature and magnification of the image of the object? (Figure down as schematic and not to scale)

$$2R = 16\text{ cm} \implies R = 8\text{ cm}$$

$$f = -\frac{R}{2} = -4\text{ cm}$$

$$u = -10\text{ cm}$$

$$\frac{1}{v} + \frac{1}{u} = \frac{1}{f} \implies \frac{1}{v} + \frac{1}{-10} = \frac{1}{-4}$$

$$\frac{1}{v} = -\frac{1}{4} + \frac{1}{10} = \frac{-5 + 2}{20} = -\frac{3}{20} \implies v = -\frac{20}{3}\text{ cm} \approx -6.67\text{ cm}$$

$$m = -\frac{v}{u} = -\frac{-20/3}{-10} = -\frac{2}{3}$$

Since $$v < 0$$, the image is real.
Since $$m < 0$$, the image is inverted.
Since $$|m| < 1$$, the image is unmagnified (diminished).