At the mall, Leona bought a T-shirt and a book for a total of $23. The book cost $12. How much did the T-shirt cost?

What is the unknown information?

Let x represent the unknown information. Write an addition equation that models the problem

Solve the equation.

Answer the question.

12 + x = 23

So, what do you think?

23-12 = cost of t-shirt.

x+12 = 23.

The unknown information in this problem is the cost of the T-shirt.

To set up an equation, we can let x represent the cost of the T-shirt. Since Leona bought a T-shirt and a book for a total of $23, we can write the equation:

x + $12 = $23

To solve the equation, we need to isolate the variable x. We can do this by subtracting $12 from both sides of the equation:

x + $12 - $12 = $23 - $12
x = $11

Therefore, the T-shirt cost $11.

Answer: The T-shirt cost $11.