RR 14 is related to UN 3 in a certain way. In the same way, BV 10 is related to ER −1. To which of the given options is PE 1 related, following the same logic?
The cost of 15 pens and 6 pencils is ₹291. If the cost of a pen decreases by ₹9 and the cost of a pencil increases by ₹2, then the cost of 9 pens and 3 pencils is ₹75. What is the original cost of 12 pens and 3 pencils?