Solve for r
r = \frac{40}{3} = 13\frac{1}{3} \approx 13.333333333
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3r=5\left(2\times 3+2\right)
Multiply both sides of the equation by 15, the least common multiple of 5,3.
3r=5\left(6+2\right)
Multiply 2 and 3 to get 6.
3r=5\times 8
Add 6 and 2 to get 8.
3r=40
Multiply 5 and 8 to get 40.
r=\frac{40}{3}
Divide both sides by 3.
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