Rakesh went to a stationary shop to purchase a total of 38 pens, erasers and sharpeners. He purchased at least 11 items of each. He purchased more sharpeners than erasers and more erasers than pens. If each pen cost Rs. 2 each eraser cost Rs. 3 and each sharpener cost Rs. 4. find the minimum expenditure be could have incurred on the items (in Rs.)