If an 18 foot pole casts a 5 foot shadow, how tall is the tree that casts a 20 foot shadow?
2006-11-25 09:25:20 · 6 answers · asked by Geneva S 1 in Education & Reference ➔ Homework Help
18:5=x:20
x=18*20/5
x=72 feet
2006-11-25 09:29:06 · answer #1 · answered by CosmicLove 5 · 0⤊ 2⤋
Yes, it is. This question is based on triangulation. The 18 foot pole forms a 90 degree angle with the ground, and casts a 5 foot shadow.
You know that the tree will also form a 90 degree angle with the ground, so it is all going to be a matter of ratios.
What is the ratio of an 5 foot shadow to a 20 foot shadow? Apply that same ratio to the 18 foot pole to find the height of the tree.
Do you now understand what you are being asked to do? Does this explanation help you with the solution? I certainly hope so.
2006-11-25 09:36:28 · answer #2 · answered by old lady 7 · 1⤊ 0⤋
Cross multiply
Tall Shadow
18 5
X 20
X= 20. 18 / 5 = 72
So the tree is 72 foot
2006-11-25 09:48:50 · answer #3 · answered by fldrod 3 · 0⤊ 0⤋
An equality.
18/5=X/20 cross mutiply
360=5X divide 5 from each side
72 feet = X
2006-11-25 09:31:31 · answer #4 · answered by Anonymous · 0⤊ 2⤋
its simple 5x4=20
4x18=72
72 feet
2006-11-25 09:40:45 · answer #5 · answered by Anonymous · 0⤊ 0⤋
72 feet IF it is the same time of day
2006-11-25 09:29:10 · answer #6 · answered by Clarkie 6 · 0⤊ 1⤋