School Supplies: Junior maths puzzle

If 1 Pencil + 1 Eraser = Rs. 10;
2 Erasers + 1 Sharpener = Rs. 13; and
2 Sharpeners + 2 Pencils = Rs. 22.
How much should I pay to buy one pencil, one eraser and one sharpener?

Write your answer in the comments below!