KöMaL 2020 C1615

The text was changed. The correct text: Julie's grandmother bakes cookies every Monday. She always selects out of her infinite number of recipes at random. $60\%$ of her recipes contain chocolate chips. Julie is quite picky about cookies: she only likes $90\%$ of grandma's chocolate chip cookies, and only $30\%$ of the other kinds of cookies. On a special Monday, grandmother is making two different kinds of cookies. Find the probability that Julie will like exactly one of them.