To find the height of the rollercoaster in Ellie's model, we need to convert the real height of the rollercoaster (475 feet) into inches using the scale given (1 inch represents 25 feet).
First, we divide the real height by the scale factor:
\[ \text{Height in model} = \frac{\text{Real height}}{\text{Scale factor}} = \frac{475 \text{ feet}}{25 \text{ feet/inch}} = \frac{475}{25} = 19 \text{ inches} \]
Therefore, the peak of the rollercoaster in her model should be 19 inches tall.