p = 20.0 cm, f = 12.0 cm
1/p + 1/q = 1/f
1/20 + 1/q = 1/12
1/q = 1/12 - 1/20 = (20 - 12)/(12X20) = 8/240
q = 240/8 = 30.0 cm

Now find the magnification:
m = -q/p = -30/20 = -1.5
i.e., Image is magnified and inverted as in the figure.

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