Problem: a ratio between two numbers is 4 : 5 and their l . c . m . is 200 . the first number is
Rationale: "sol . let the required numbers be 4 x and 5 x . then , their l . c . m . is 20 x . ∴ 20 x = 200 ⇔ x = 10 . hence , the first number is 40 . answer b"
annotated_formula: multiply(divide(200, multiply(4, 5)), 4)