Solve for r
r=\frac{33}{40}=0.825
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80r-2=64
Swap sides so that all variable terms are on the left hand side.
80r=64+2
Add 2 to both sides.
80r=66
Add 64 and 2 to get 66.
r=\frac{66}{80}
Divide both sides by 80.
r=\frac{33}{40}
Reduce the fraction \frac{66}{80} to lowest terms by extracting and canceling out 2.
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