If you're a woman 29 or younger, great looking and have a minimum SAT score of 1,300, Jim Cramer told his "RealMoney" radio show listeners Thursday, a money-making opportunity is out there. Egg donation is booming he said, and the fertility industry has been going through a boom cycle as companies pay $2,000 to $10,000 for unfertilized eggs. And according to a story in USA Today, there are many attractive, intelligent college age women donating eggs to pay off school loans. But you don't have to be a potential egg donor to make money here, Cramer said. "When I hear about the demand for fertility, I think about Serono ( SRA), an $18 stock with a billion-dollar franchise to help women become more fertile," he said. If indeed the fertility business is getting stronger and there's more demand, this is your play, he said, even though Wall Street doesn't care for the stock. Cramer believes that the earnings growth is solid, and as an added bonus, he said it could even be a takeover target. A listener wanted help with reading an earnings report. Cramer offered a lemonade stand analogy, saying that the cost of the materials needed for the lemonade -- lemons, sugar, water -- as well as the time dedicated to the enterprise, are the raw costs. If $10 worth of lemonade is sold, that's the revenue, he said. If the raw costs come to $3, then the profit is $7. If you have a fancy lemonade stand and you have to keep investing, that will produce something called amortization, he said. As for the term "balance sheet," Cramer said to imagine walking into the bank and saying that you pull in $1,500 a month but want a mortgage for a house that is $2,000 a month. Then you're $500 short, he said, and that is not typically a healthy balance sheet. We look at a balance sheet to see who is short, Cramer said. "The only place to find out whether you have a loser or a winner is on the balance sheet." It is essential to see whether a company pulls in more than it owes creditors and banks.