Answer
a) yes
b) no
c) yes
d) yes
Work Step by Step
a) The numbers 11, 15=3*5, and 19 are pairwise relatively prime because there are no factors shared between two of them.
b) The numbers 14=2*7, 15=3*5, and 21=3*7 are not pairwise relatively prime because both 15 and 21 have a factor of 3.
c) The numbers $12=2^2*3$, 17, 31, and 37 are pairwise relatively prime because no two of them share a factor.
d) The numbers $7, 8=2^3, 9=3^2,$ and 11 are pairwise relatively prime because none of them share a factor with any of the others.
