The cost of 1lb of strawberries is a dollar more than the cost of 1lb of grapes. If ms. A bought 2lbs of strawberries and 5lbs of grapes for $12.50. What is the cost of the fruits.
cost of grapes --- x per lb
cost of berries --- x+1 per lb
2(x+1) + 5x = 12.5
solve for x