Relative density of pure gold = 19.3
Weight of the bangle in air (W1) = 25.25 gf
Weight of the bangle in water (W2) = 23.075 gf
RD of Bangle = W_1\over W_1-W_2
= 25.25\over 25.25-23.075
= 25.25\over 2.175 = 11.6
It is given that relative density of gold is 19.3 where as relative density of bangle is 11.6.
Hence, we can deduce that the bangle is not made of pure gold.