25/2 x 10/1= 1.25 sorry I fluctuated between fraction and decimal! Lol
If there are 12.5 lbs of potatoes and 1/10 of that is the butter, divide 12.5 by 10 to get 1.25 lbs butter.
Ellie uses 1.25 pounds of butter, which is one-tenth of the 12.5 pounds of potatoes she has.
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