Question

a crown made of gold and a copper weight 210 gm in air and 198 gm in water .the weight of gold in crown is?...solve the problem

Answer 1

Density of gold : 19.3 g/cc.

Density of copper : 8.5 g/cc.

The loss of weight : 210 g -198 g = 12 g

mass Gold / 19.3  + mass Copper / 8.5 = 12 g

G / 19.3 + C / 8.5 = 12  and G + C = 210

C = 210 - G

( 8.5 G + 19.3 C ) / 164.05 =12

8.5 G + 19.3 ( 210 - G ) = 1968.6

8.5 G + 4053 - 19.3 G = 1968.6

10.8 G = 2084.4

G = 2084.4 : 10.8 = 193 g

Answer:  The weight of gold in crown is 193 g.