Christy drove 132 miles in 2 3/4 hours what was her average speed in miles per hour?
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let's first convert the mixed fraction to improper, and get their quotient.
[tex] \bf \stackrel{mixed}{2\frac{3}{4}}\implies \cfrac{2\cdot 4+3}{4}\implies \stackrel{improper}{\cfrac{11}{4}} \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \cfrac{132}{~~\frac{11}{4}~~}\cfrac{miles}{hours}\implies \cfrac{\frac{132}{1}}{~~\frac{11}{4}~~}\implies \cfrac{132}{1}\cdot \cfrac{4}{11}\implies \cfrac{132}{11}\cdot \cfrac{4}{1}\implies 12\cdot 4\implies 48\frac{miles}{hours} [/tex]