We know that our consumer will buy pairs of socks for which the marginal utility is greater than the market price, and will not buy pairs for which the marginal utility is below the market price. The table to the right only gives total utility. Is this enough information to determine how many pairs she'll buy at various prices? Yes, and the solution is simple enough. Remember that marginal utility is just the added utility from consuming one more unit of a good, so the table gives us all the information we need to compute marginal utility for each added pair of socks.