SOLUTION: A person 5 feet 3 inches tall casts a 6-foot shadow. At the same time, a lamppost casts an 18 foot shadow. What is the height of the lamppost?

Question 1169111: A person 5 feet 3 inches tall casts a 6-foot shadow. At the same time, a lamppost casts an 18 foot shadow. What is the height of the lamppost?

Answer by greenestamps(13203) (Show Source): You can put this solution on YOUR website!

At any given time, all the sun's rays are pointing at the same angle.

So, assuming level ground, the ground, the sun's rays, the person, and the lamppost form similar triangles.

In similar triangles, the ratios of corresponding sides are all the same. A shadow 3 times as long (18 feet instead of 6 feet) means the object is 3 times as tall.

Do the arithmetic....

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