Explanation:
1/16 for Washington County.
5/76 for Webster County.
so, let's bring both to the same denominator (bottom part of the fractions).
this is usual the LCM of both denominators.
since 16 = 2×2×2×2
76 = 2×2×19
the least common multiple (LCM) is the combination of the longest sequence per prime factor involved :
2×2×2×2×19 = 16×19 = 304
1/16 = 19/304
5/76 = 5× 1/76 = 5× 4/304 = 20/304
so, now we know, 20/304 > 19/304, and therefore Webster County has the greater fraction of adults, who enjoy gardening.