Mia used
lb of flour to bake the chocolate cake.
<h3>
Further Explanation</h3>
Given:
Total flour
lbs
She used:
for banana cake
x lbs for chocolate cake
Flour left
lbs
How much flour did she use to bake the chocolate cake?
so the flour that Mia use for banana cake is total flour subtract the flour that she used plus the left over.
x =Total flour - flour for banana cake - left over

I am going to put this into improper fraction

because the denominator is different, we are going to find the common denominator for 9, 4 and 6 which is 36

So the flour that she use to bake the chocolate cake is
lbs
<h3>Learn More</h3>
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Keyword: mixed fraction, subtraction, improper fraction, part to whole relationship