Explanation:
gallons to quarts have the ratio 1:4.
there are 4 quarts in a gallon (hence the name of quarts by the way).
so, the question is really, which order pair have also a 1:4 ratio between x and y ?
(1, 4)
(2, 8)
(3, 12)
the (4, 1) would represent a 4:1 ratio.
and as you know, 4/1 is different to 1/4.
a ratio is nothing else than a fraction. just the "whole" is different.
the pure fraction 1/4 means that the whole is 4/4, has 4 times 1/4.
a ratio 1:4 (you can also write as 1/4) means that the whole has 5 (1+4) parts.
other than that they are compared and calculated with the same way as normal fractions.