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12 votes
12 votes
The height of a street light is 23 feet. It casts a 12-foot shadow. At the same time, a man

standing next to the street light casts a 3-foot shadow. How tall is the man? If needed,
round the answer to the nearest hundredth.
The man is
feet tall.

User James Brierley
by
3.3k points

1 Answer

12 votes
12 votes

Explanation:

this creates 2 similar triangles.

that means all angles are the same. and all the side lengths of one triangle correlate to the corresponding side lengths of the other triangle by the same multiplication factor.

3 × f = 12

f = 12/3 = 4

now, the same factor applies also to the relation of the heights :

x = height of the man

x × 4 = 23

x = 23/4 = 5.75 ft

the man is 5.75 ft (= 5' 9") tall.

User Dfcorbin
by
2.4k points