Combined, Natalie and Ellie sold 90 boxes of Girl Scout cookies. If Natalie sold one-third of this, find the ratio of the boxes of cookies that Natalie sold to the number of boxes that Ellie sold.
Let Natalie = n, Ellie = e
n + e = 90
90/3 = n
n = 30
30 + e = 90
e + 30 (-30) = 90 (-30)
e = 60
Natalie sold 30, Ellie sold 60
30:60 simplified = 1:2
For every one Natalie sells, Ellie sells 2
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