Final answer:
To find the scale factor for enlarging a children's book from 20 cm by 24 cm to 25 cm by 30 cm, divide the enlarged dimension by the original corresponding dimension, resulting in a scale factor of 1.25.
Step-by-step explanation:
We are asked to find the scale factor used to enlarge a children's book from dimensions of 20 cm by 24 cm to a larger version with dimensions of 25 cm by 30 cm. To find the scale factor, we need to divide one dimension of the enlarged book by the corresponding dimension of the original book. We can take either the length or the width to find the scale factor.
Let's use the width for this example:
Original width = 20 cm
Enlarged width = 25 cm
Scale factor = Enlarged width / Original width
Scale factor = 25 cm / 20 cm
Scale factor = 1.25
Therefore, a scale factor of 1.25 should be used to enlarge the book from the original dimensions to the new dimensions.