The scale factor of ABC to DEF would be 1/3 Thus, the correct option is B.
What is the scale factor?
The scale factor states the scale or measurement by which a figure is bigger or smaller than the other figure. The size by which the figure would be reduced or enlarged is called its scale factor.
In a triangle ABC and DEF
The sides are as follows 5 to 15 which is thrice the length of the side in ABC.
4 to 12 which is 3 times the length of the side in ABC.
3 to 9 which is 3 times the length of the side in ABC.
Thus, the scale factor would be 1/3.
Learn more about scale factors;
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