The true statement is that Alex is 50% taller than Dan.
They both measured themselves against a tree in their backyard.
Therefore, the tree is 80% taller than Dan and 20% taller than Alex.
Hence,
let
Dan height = x
Tree's height = x + 0.8x
Tree's height = 1.8x
let
Alex height = y
Tree's height = y + 0.2y
Tree's height = 1.2y
Therefore, if we use Dan height as 100, the height of the tree will be 180.
Then,
180 = 1.2y
y = 150
This means Alex is 50 percent taller than Dan.
learn more on percentage here: https://brainly.com/question/14177792
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