A boy spent half his money for a book and one third his money for a pen. The remaining $2.25 he saved. How much money did he have originally?

1 answer

Let's denote the original amount of money the boy had as "x" dollars.

According to the problem, he spent half of his money on a book, so he spent (1/2)x dollars on the book.
He also spent one-third of his money on a pen, so he spent (1/3)x dollars on the pen.

The total amount of money he spent on the book and the pen is (1/2)x + (1/3)x = (5/6)x dollars.

We know that the remaining amount of money he saved is $2.25, so we can set up the equation (5/6)x = $2.25.

To solve for x, we can multiply both sides of the equation by 6/5: x = 6/5 * $2.25.

Multiplying, we find x = $2.70.

Therefore, the boy originally had $2.70. Answer: \boxed{2.70}.