Profit Loss

A contractor estimates that a job will earn him Rs 8400. His estimate covers material, labour and 5% profit. The cost of material and labour is in the ratio of 3 : 7. When the contractor begins his job, however, he discovers that the cost of material has increased by 10% and the labour cost has risen by 15%. Calculate his loss percent

  1. 7.36%
  2. 7.59%
  3. 7.49%
  4. 7.39%

Answer

5% profit = Rs.8400

Let estimated cost be Rs.x

5% of x = 8400

Estimated Cost, x = 168000

Average increase in cost = (3*10 + 7*15)/10 = 13.5%

New Cost = 168000*113.5% = 190680

Loss = 190680 - 168000 - 8400 = 14280

Loss % = 14280/190680 = 7.49%

The correct option is C.