In what ratio must a grocer mix two varieties of pulses costing Tk. 15 and Tk. 20 per kg respectively so as to get a mixture worth Tk. 16.50 kg?

Question: In what ratio must a grocer mix two varieties of pulses costing Tk. 15 and Tk. 20 per kg respectively so as to get a mixture worth Tk. 16.50 kg?Solution:Let 15 Tk kg pulses = x kg and 20 Tk kg pulses = y kg ATQ,15x + 20y = 16.5(x + y) ⇒ 15x + 20y = 16.5x + 16.5y ⇒ 1.5x = 3.5y ⇒ x/y = 3.5/1.5 ⇒ x/y = 7/3⇒ x : y = 7 : 3