Answer:
40 ft
Step-by-step explanation:
The tree's shadow is 60/12 = 5 times the length of the shadow of the post. So, we figure the tree is 5 times the height of the post:
5(8 ft) = 40 ft . . . height of tree
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You may want to write a proportion:
tree height/tree shadow = post height/post shadow
t / 60 = 8 / 12
t = 60(8/12) = 40 . . . . multiply by 60
