Quadrilateral ABCD in the figure below represents a scaled-down model of a walkway around a historic site. Quadrilateral EFGH represents the actual walkway. ABCD is similar to EFGH. Two irregular similar quadrilaterals ABCD and EFGH are drawn. AB measures 6 inches, BC measures 3 inches, CD measures 3 inches and DA measures 4 inches. EF measures 72 feet. What is the total length, in feet, of the actual walkway?
|dw:1607618816209:dw| Is this what it looks like?
yes
First off, we know ABCD and EFGH are similar
The only difference is they're scaled differently
We know that the ratio between each corresponding segment will be the same.
we also know that AB is 6 inches, and that EF is 72 feet
wait, so how do i find the sides on the bigger shape
We have to use what we already know about the smaller shape to find the sides of the bigger one
hmm, so everything on the smaller shape is half of the bigger shape?
like if they divided the numbers in half
Not quite,
Okay, as I said earlier we know the ratio between each corresponding segment will be the same. and that EF is 72 feet, so the ratio is 144 (72/6 = 12, then 12 inches per foot) Meaning EF is 12 times longer (in feet) than AB is (in inches)...
Are you following?
yes, so then GF would be 36 because it would also be 12 time longer then CB? because AB times 12 get you 72 which is EF
Yeah, here: are the steps EF = 72 ft FG = 36 ft (3 * 12) GH = 36 ft (3 * 12) EH = 48 ft (4 * 12)
So, now we know that the total length of the pathway is: 72 + 36 + 36 + 48 = 192 feet
oh, okay i get it now, thank you!
Np! can I get a medal?
how do i do that
Thank you!
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