To find the distance between two numbers on the number line, you can use the formula:
\[ \text{Distance} = |a - b| \]
where \( a \) and \( b \) are the two numbers. In this case, \( a = 18.25 \) and \( b = -7.4 \).
Now, calculate the distance:
\[ \text{Distance} = |18.25 - (-7.4)| = |18.25 + 7.4| = |25.65| \]
Thus, the distance between 18.25 and -7.4 on the number line is 25.65.