Pacific Coast Railway has fixed costs of $70,000 per month. Each passenger generates a $20 variable cost and tickets are sold for $100 each. For the railway to earn an operating income of $180,000 per month, it must generate $312,500 in revenue. This is calculated by determining the contribution margin ratio is 80% and that revenue of $312,500 would cover the $250,000 of fixed costs plus the target operating income.