In a factory there are 100 skilled 150 semi skilled and 250 unskilled workers. It has been observed that on an average a unit length of particular fabric is woven by skilled worker in 3 hrs, by a semi...

In a factory there are 100 skilled 150 semi skilled and 250 unskilled workers. It has been observed that on an average a unit length of particular fabric is woven by skilled worker in 3 hrs, by a semi skilled in 4 hrs and unskilled in 5 hrs. After a training of 2 years the semi skilled workers are expected to become skilled and unskilled to become semi skilled. How much less time will be required after 2 years of training for weaving the unit length of fabric by an average worker