Answer: Hello there!
We know that the number of blueberries picked varies directly as the number of hours worked.
Direct variation means that: b = kh
where b is the number of blueberries, k is a constant of proportionality and h is the number of hours worked.
we know that in 10 hours there are 30 pounds of blueberries collected, then we can replace these numbers in the equation and solve it for k. And you want that I don't include units in the answer, so I will not include them.
30 = k*10
k = 30/10 = 3
Then the constant of proportionality is 3, whit is the amount of punds of blueberrys collected in one hour.