Jessica buys coffee for $1 a cup and tea for $2 a cup. Every day she buys 2 coffees and 4 teas, exhausting her $10 income. Kareem, whose income is also $10, buys coffee for $3 a cup and tea for $1 a cup. But he'd be happier if he could buy at the prices Jessica pays. Can you determine whether Jessica and Kareem have different tastes?