Given:
The price of two articles are in the ratio of 3 : 2 respectively
Formula Used:
Selling price = Cost price + profit
Selling price = Cost price – loss
Calculation:
Let the cost price of two articles be 3y and 2y respectively, then
When the price of first article is increased by 40%
Price of first article = 3y + (40/100) × 3y = 4.2y
When the price of second article is decreased by x%
Price of second article = 2y – (x/100) × 2y = 2y – 2xy/100
Now,
⇒ (4.2y)/(2y – 2xy/100) = 7 : 3
⇒ 12.6y = 14y – 14xy/100
⇒ 14xy/100 = 1.4y
⇒ x = 10%
∴ Value of x is 10
Alternate Method Let the cost price of two articles is = 300y & 200y
When the price of first article is increased by 40%
Price of first article = 300y x 1.4 = 420y
When the price of second article is decreased by x%
Price of second article = 200y(1 – (x/100))
As per the question,
200y(1−100x)420y=37
200180=(1−100x)
x = 10