Dave has 12$ to spend on a 7 dollar book and two birthday cards (c) for his friends how much can he spend on each card if he buys the same card for the each friend
So if you have a budget of 12 dollars, and the book is 7 dollars, subtract 12-7 and you get 5 dollars. And half of 5 dollars is 2.50. And if there is 2 cards, then that means that 1 card is 2.50