in a garden 1/3 of the purple flowers equals to 1/6 of the total number of flowers. 1/4 of the blue flowers equals to 1/7 of the total number of flowers.
what is the ratio between the purple flowers and the blue ones?

isn't it a problem that half are purple and more than half are blue? that means that there must be some blue purple flowers and that's not indicated as a possibility. the question implies that blue is only blue, and purple is only purple.