F = Cup of flour
D = Dinner roll(s)
12 = A dozen
36 = Three dozen
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1/3 F = 5 D
n F = 36 D
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\(\frac { 1 }{ 3 } F=5D\\ \\ 3\cdot \frac { 1 }{ 3 } F=3\cdot 5D\\ \\ F=15D\)
\(nF=36D\\ \\ n=\frac { 36D }{ F }\)
This means that...
\(n=\frac { 36D }{ 15D } \\ \\ n=\frac { 36 }{ 15 } \\ \\ n=\frac { 3\cdot 12 }{ 3\cdot 5 } \\ \\ n=\frac { 12 }{ 5 } \\ \\ n=\frac { 10 }{ 5 } +\frac { 2 }{ 5 } \\ \\ n=2+\frac { 2 }{ 5 }\)
And this means that two cups of flour and 2/5 of a cup of flour are required to make 3 dozen dinner rolls.
