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If a 40 foot tree cast a 16 foot shadow, what is the length of the shadow cast by a 27 foot tree?

User Mommermi
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2 Answers

7 votes
I take it that we are to assume that the ratio between the actual length and the shadow length are directly proportional


so therefor we set up the following proprtion

actual height: shadow height=40ft:16ft

we are given that the tree is actually 27ft

so
40ft:16ft=27ft:?ft
make into a fraction
40ft/16ft=27ft/?ft
cross multiply or multiply both sides by 16?ft²
40?ft²=432ft²
divide both sides by 40ft
?ft=10.8ft
the length of the shadow is therfore 10.8ft
User DallaRosa
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6 votes

this is a ratio:

40/16 = 27/x

cross multiply:

40x = (16*27)=

40x=432

x = 432/40 = 10.8 feet

User Lejla
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