Let 2x m of trouser material and 3x m of shirt material be bought by him.
Per metre selling price of trouser material
= Rs(90 + 90 x 12/10) = Rs 100.80
Per metre selling price of shirt material
= Rs (50 + 50 x 10/100) = Rs 55
Given that, total amount of selling = Rs 36660
100.80 × (2x) + 55 × (3x) = 36660
201.60x + 165x = 36660
366.60x = 36660
Dividing both sides by 366.60, we obtain
x = 100
Trouser material = 2 x m = (2 x 100)m = 200m