Answer:
The farmer must sell at least 25 quarts of berries and 50 heads of lettuce to take in $150 or more for the day.
Step-by-step explanation:
Revenue = (unit cost)(number of units)
The unit cost for quarts of strawberries is $3.50; represent the number of quarts sold by q.
The unit cost for heads of strawberries is $1.25; represent the number of quarts sold by h.
Then q + h = 75 (items); we could solve for q in terms of h, obtaining
q = 75 - h.
Total revenue is then
($3.50/quart)q + ($1.25/h)h ≥ $150
Then 3.50q + 1.25(75 - q) ≥ 150, or
2.25q + 93.75 ≥ 150, or
2.25q ≥ 56.25
Solving for q, we divide both sides by 2.25, obtaining q ≥ 25.
Since q + h = 75, h = 75 - q, or 75 - 25, or h = 50.
The farmer must sell at least 25 quarts of berries and 50 heads of lettuce to take in $150 or more for the day.