Final answer:
Yan's height is 36 inches.
Step-by-step explanation:
To find Yan's height, we can use the concept of similar triangles.
Since Yan's dog is 24 inches in front of him and its shadow is 18 inches long, we can set up a proportion to find Yan's height.
Let x represent Yan's height.
We have the following proportion:
(x / 24) = (27 / 18).
Cross-multiplying gives us 18x = 24 * 27.
Simplifying, we have 18x = 648.
Dividing both sides by 18 gives us x = 36.
Therefore, Yan is 36 inches tall.