The purple gene in Drosophila specifies the normal and red eyes (for the dominant pr+ allele) and purple eyes ( for the recessive pr allele). Another gene called the vestigial gene specifies normal, long wings (for dominant vg+ allele) and short wings (for recessive vg allele). A double heterozygous female mates with a tester (homozygous recessive for both genes) and yields the following offspring:

     pr+ vg+ and pr vg: 1422
     pr vg and pr vg: 1032
     pr+ vg and pr vg: 134
     pr vg+ and pr vg: 139

What is the recombination frequency between the purple and vestigial genes?