https://preparationpoint.info/solved-past-papers-mcqs/ppsc-past-papers/ppsc-past-papers-2018/excise-taxation-inspector-bs-16-2018-in-additional-directorate-held-on-20-10-2018/the-price-of-2-pens-and-3-pencils-is-86-the-price-of-4-pens-and-1-pencil-is-112-find-the-price-of-a-pen/