NPR Weekend Edition Sunday Puzzle
September 23, 2018
Will Shortz

The following two-word phrases share a very unusual property. Can you determine what it is?

PROPERTY RIGHTSLAND MINE
SALES ORDER
COLOR SCHEME
INDIA INK

HINTS:
1. It has to with the first three letters of the first words.
2. ............ and the first two letters of the second words.
3. U.S. geography

Answer:

In each phrase, the first three letters of the first word are the first three letters of a state capital, and the first two letters of the second word are that capital's state postal abbreviation:

PROvidence, RIghts
LANsing, MIchigan
SALem, ORegon
COLumbia, South Carolina
INDianapolis, INdiana 

Note: This puzzle, in its original form - without the hints, was a tough one for NPR listeners. It received only 100 correct answers - far fewer than the usual amount.