Hasan buys two kinds of cloth materials for school uniforms,shirt material that costs him₹50 per metre and trouser material that costs him₹90 per metre.For every 3 metres of the shirt material be huys 2 metres of the trouser material.He sells the materials at 12% and 10% profit respectively.His total sale is ₹36,600.How much trouser material did he buy?

The resistance per metre length of a wire is 10 Omega . If the resistivity of the material of the wire is 50 xx 10^(-8) ohm metre, find the area of cross- section of the wire.

In a development plan of a city, a contractor has taken a contract to construct certain houses for which he needs building materials like stones, sand etc. There are three firms A, B, C that can supply him these materials. At one time these firms A, B, C supplied him 40, 35 and 25 truck loads of stones and 10, 5 and 8 truck load of sand respectively. If the cost of one truckload of stone and sand are Rs 1200 and 500 respectively, then find the total amount paid by the contractor to each of these firms A, B, C separately.