Question - Basic Arithmetic Problem on Summer Reading

Let the total number of books Ada wants to read be \( T \).

Let the number of books about cats be \( C \).

Let the number of books about horses be \( H \).

According to the problem, \( T = 12 \) and \( C = 5 \).

To find \( H \), we subtract the number of books about cats from the total number of books:

\( H = T - C \)

\( H = 12 - 5 \)

\( H = 7 \)

Therefore, \( 7 \) books are stories about horses.