Answer:
1/7 acre
Explanation:
The number of acres planted is presumed to be proportional to the number of pounds of seeds:
acres/pounds = 8/56 = x/1
x = 1×8/56 = 1/7
1/7 acre can be planted per pound of seed.
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Additional comment
When you recognize that 56 = 8×7, there is a tendency to want to divide 56 by 8. That would result in the unit rate ...
(56 lb)/(8 ac) = 7 lb/ac
That is, it takes 7 pounds of seed to plant 1 acre. The question asks how many acres can be planted with 1 pound. Clearly, that is 1/7 of the amount of seed required for 1 acre, so 1 pound will plant 1/7 acre.