A landscape architect is planning a new nature area in the middle of an urban campus. She wants the length to be twice the width and wants to put a 3 foot high retaining wall around the perimeter. There will be 300 total feet of wall installed. How wide will this area be?

sounds like it's a rectangle.

total = length x width x height

using length = twice the width:

total = (2 x width) x width x height
total = 3 x width x height

you know the height and total. solve for width

It's a perimeter wall, not an area. So it's 2 x (width + length) x height
So total = 2 x ( width + 2 width) x height
total = 6 x width x height

This post was edited by russian on Oct 17 2016 11:51pm

The height of the wall has to be a mislead, right?

Perimeter of this assumed rectangle is width + width + height + height

height = 2x width (in which case)

permeter = 6x width = 300 ft

width = 50 ft, height = 100 ft, 100+100+50+50=300

This post was edited by thesnipa on Oct 18 2016 11:43am

Dunno. When they say "feet of the wall", do they mean just feet of length, or square feet? If they threw in the height as a mislead, then it's really terribly worded.

Intermediate math is full of misleads from what i've seen, they're often put in or omitted to make the child think critically about what the answer should be and what formula's they need. Its a dirty trick but it does make kids better thinkers.

I guess. I think too many times the authors are trying to come up with some stupid "gotcha" that doesn't really do anything and makes adults roll their eyes. Shit like "If there are 5 pineapples growing on a tree and 3 of them fall down, how many are still on the tree? None, because pineapples don't grow on trees".
I'm totally OK with misleads like irrelevant data, when it's clear that the data is irrelevant if you understand the math behind the problem. So it will get any kid that just tries to throw all the numbers he has into a calculator, but disregarded by anyone who knows what to do. In this particular case, I fully understand the math but I'm still not sure whether they mean feet of length of wall or feet of area of wall. I guess length would be more typical for conversational English?