Let the weight of zinc in the brass utensil be x gm. Since, the ratio of the weights of copper to zinc in brass is 13:7.
∴ Weight of copper in the brass utensil = \(\cfrac{13x}{7}\) gm The weight of the brass utensil = 700 gm
∴ \(\cfrac{13x}{7}\)+ x = 700
∴ \(\cfrac{13x}{7}\) x × 7 + x × 7 = 700 × 7
∴ 13x + 7x = 4900
∴ 20x = 4900
∴ x = \(\cfrac{4900}{20}\)
∴ x = 245
∴ The weight of zinc in the brass utensil is 245 gm.
