The ratio of prices of Cello and Rotomac pens in 2000 were in the ratio of 3 : 5.
Posted on 12-02-2023
Ques - The ratio of prices of Cello and Rotomac pens in 2000 were in the ratio of 3 : 5. In 2005 the price of Cello pen trebles itself and the price of Rotomac pen is increased by Rs. 100, then the new ratio of prices of the same pens becomes 4 : 5. What was the original price of the Rotomac pen in 2000?
(a) Rs. 60
(b) Rs. 80
(c) Rs. 100
(d) Rs. 120
Solution -
The ratio of prices of Cello and Rotomac pens in 2000 = 3 : 5
Let,
The price of Cello pen in 2000 = 3x
The price of Rotomac pen in 2000 = 5x
In 2005,
The price of Cello pen = 3(3x)
= 9x
The price of Rotomac pen = 5x + 100
Then,
The new ratio of prices = 4 : 5 (given)
(9x)/(5x + 100) = 4/5
5(9x) = 4(5x + 100)
45x = 20x + 400
45x - 20x = 400
25x = 400
x = 16
Therefore,
The original price of rotomac pen in 2000 = 5x
= 5(16)
= 80
Hence,
The correct answer is option (b) Rs. 80.
Thank You