Bob and maria go to the fruit stand together. they have at most $21 to spend on fruit to make muffins. blueberries cost $4 per pound and strawberries cost $3 per pound. they need at least 3 pounds of fruit. bob says they should buy 1 pound of blueberries and 3 pounds of strawberries.

maria says they should buy 2 pounds of each.

are both of these possible?