Let the price of an adult ticket be \( x \) dollars.
The total cost for the 4 student tickets is: \[ 4 \times 7 = 28 , \text{dollars} \]
The total cost for the 3 adult tickets is: \[ 3 \times x \]
According to the problem, the total cost for the tickets is $64. Therefore, we can set up the equation: \[ 28 + 3x = 64 \]
To solve for \( x \), first, subtract 28 from both sides: \[ 3x = 64 - 28 \] \[ 3x = 36 \]
Now, divide both sides by 3: \[ x = \frac{36}{3} = 12 \]
Thus, the cost of each adult ticket is \( \boxed{12} \).