Answer:
Step-by-step explanation:
Let x represent the number of meters of shirt material that he bought.
Let y represent the number of meters of trouser material that he bought.
For every 3 metres of the shirt material, he buys 2 metres of the trouser material. It means that
2x = 3y
x = 3y/2
shirt material cost him ₹ 50 per metre and trousers material cost him ₹ 90 per metre. It means that the total cost is
50x + 90y
Selling price for the shirt material is
50x + (12/100 × 50x) = 56x
Selling price for the trouser material is
90y + (10/100 × 90y) = 99y
If his total sale is ₹ 36,600, it means that
56x + 99y = 36600- - - - - - - - 1
Substituting x = 3y/2 into equation 1, it becomes
56(3y/2) + 99y = 36600
Multiplying both sides by 2, it becomes
168y + 198y = 73200
366y = 73200
y = 73200/366
y = 200
x = 3y/2 = 3 × 200/2
x = 300
He bought 200 meters of trouser material