IMAS 2020–2021 Junior Division — First Round Question 10

If the cost to buy 2 pens, 3 ballpens and 5 notebooks in a stationery store is 44 dollars and the cost to buy 3 pens, 7 ballpens and 10 notebooks is 81 dollars. How much does it cost to buy 1 pen, 3 ballpens and 4 notebooks?