MHB Find the scale factor of triangle ABC to triangle DEF

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Triangles ABC and DEF are similar, with triangle ABC having a perimeter of 16 cm and triangle DEF having sides of 6 cm, 8 cm, and 10 cm, totaling a perimeter of 24 cm. The scale factor of triangle ABC to triangle DEF is determined to be 2/3 based on the perimeter ratio of 16:24. There is a distinction between the dilation scale factor, which is 3/2, and the scale ratio, which is less than 1 since triangle ABC is smaller. The confusion arises from the terminology used, as the question specifically asks for the "scale factor." Therefore, the correct scale factor from triangle ABC to triangle DEF is 2/3, not 3/2.
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Triangles ABC and DEF are similar.

Triangle ABC has a perimeter of 16cm.

Triangle DEF has side of 6cm, 8cm and 10cm.

What is the scale factor of triangle ABC to triangle DEF?

A. 1/2
B. 1/3
C. 2/3
D. 3/2
E. 2/1

I concluded the answer is D. Am I correct?
 
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What is the scale factor of triangle ABC to triangle DEF?

perimeter of ABC : perimeter of DEF = 16:24 = 2:3
 
There is a difference between the "scale factor of triangle ABC to triangle DEF" and the "scale factor of triangle DEF to triangle ABC". You found the wrong one! Since ABC is smaller than DEF, the scale factor is less than 1.
 
Then, is this textbook example incorrect?
 

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The dilation scale factor, which is a transformation, of triangle ABC to triangle DEF is 3/2

The scale ratio, like a map's scale, of triangle ABC to triangle DEF is 2/3

Sorry for the confusion.
 
skeeter said:
The dilation scale factor, which is a transformation, of triangle ABC to triangle DEF is 3/2

The scale ratio, like a map's scale, of triangle ABC to triangle DEF is 2/3

Sorry for the confusion.

So, the question asked about "scale factor", not ratio of any kind. Is the answer, in fact, "D", which is 3/2?
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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