On a certain hot summers, 256 people used the public swimming pool. The daily prices are $1.75 for children and $2.75 fo adults. The receipts for admission totaled to $551.50. How many children and adults swam that day?
x = adults
256-x = children
$ 2.75 x + $ 1.75 * (256-x) = $ 551.50 solve for x = adults, then 256-x = children