Three neighbors make a fruit salad for a summer picnic. One person uses three pounds of strawberries plus five pounds of grapes plus one pound of melon at a cost of $20. A second person uses three pounds of strawberries plus two pounds of grapes plus two pounds of melon at a cost of $21. The last neighbor uses four pounds of strawberries plus three pounds of grapes plus three pounds of melon at a cost of $30. How much does each fruit cost?.
