Shortcut Trick 37.5% as a fraction is 3/8. Ratio of Silver to Total Alloy = 3 : 8. Ratio of Other Elements = 8 − 3 = 5 units. Given, 3 units = 117 gm → 1 unit = 39 gm. Other elements = 5 units = 5 × 39 = 195 gm. ∴ The correct answer is 195 gm. Alternate Method Given: Silver percentage = 37.5% Quantity of silver = 117 gm Let the total quantity of the alloy be x gm. ⇒ 37.5% of x = 117 ⇒ (37.5 ÷ 100) × x = 117 ⇒ 0.375 × x = 117 ⇒ x = 117 ÷ 0.375 ⇒ x = 312 gm ⇒ Quantity of other elements = Total quantity − Quantity of silver ⇒ Quantity of other elements = 312 − 117 = 195 gm ∴ The correct answer is 195 gm. Related Concepts: Percentage to Fraction Conversion Standard fractions like 12.5% = 1/8, 25% = 1/4, 37.5% = 3/8, 50% = 1/2, 62.5% = 5/8, 75% = 3/4, and 87.5% = 7/8 help solve percent-based mixture and alloy problems instantly. Alloy Ratio Problems For any binary mixture, if the percentage of component A is P%, the percentage of component B is (100 − P)%. The ratio of the components is A : B = P : (100 − P).