Question
There were some pens in Packet X and Packet Y. After Peter transferred 13 of the pens from Packet X to Packet Y, the ratio of the number of pens in Packet X to that in Packet Y changed to 3 : 5. Find the ratio of the numbers of pens in Packet Y to the number of pens in Packet X at first.
3 m

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There were some pens in Packet X and Packet Y. After Peter transferred 13 of the pens from Packet X to Packet Y, the ratio of the number of pens in Packet X to that in Packet Y changed to 3 : 5. Find the ratio of the numbers of pens in Packet Y to the number of pens in Packet X at first.