Problem: Rahim bought two varieties of rice, costing Taka 5 per kg and Taka 6 per kg each, and mixed them in some ratio. Then he sold the mixture at Taka 7 per kg, making a profit of 20 percent. What was the ratio of the mixture?
View all: RAJSHAHI KRISHI UNNAYAN BANK OFFICER (SO) | WRITTEN QUESTION (MATH) SOLVE | 2014
Correct Answer: 1:5
Explanation:
Let, Rahim mixed x kg, per kg Tk. 5
Total price = 5x
y kg, per kg Tk. 6
Total price = 6y
At 20% profit
If selling price 120 Tk. Then buying price would be = 100 Tk.
If selling price 7 Tk. Then buying price would be =$\frac{120×7}{100}=\frac{35}{6}$ Tk.
According to the question5x+ 6y=$\frac{35}{6}$(x +y)
=>6(5x + 6y) = 35x + 35y
=>30x + 36y = 35x + 35y
=>30x — 35x = 35y — 36y
=>— 5x = — y
=>5x = y
=> $\frac{x}{y}=\frac{1}{5}$
The ratio of mixture =1 : 5
