In a sale of lands, if the purchase is per acre, a deficiency in the number of acres may be apportioned in the price. If the sale is by the tract or the entire body, a deficiency in the quantity sold cannot be apportioned. If the sale is by a quantity of acres with the qualification "more or less" added, any deficiency is not apportionable unless the deficiency is so great as to constitute a willful deception or mistake amounting to fraud. In this event, the purchaser may demand a rescission of the sale or an apportionment of the purchase price.