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**1. Homework Statement**

A power station delivers 520 kW of power to a factory through wires of total resistance of 3ohms. How much less power is wasted if the electricity is delivered at 50000V instead of 12000V?

**2. Homework Equations**

[tex]V=IR[/tex]

[tex]P=IV=I^{2}R=\frac{V^{2}}{R}[/tex]

**3. The Attempt at a Solution**

[tex]\frac{(50000V)^{2}}{3ohms}=8.3x10^{8}W[/tex]

[tex]\frac{(12000V)^{2}}{3ohms}=4.8x10^{7}W[/tex]

[tex]8.3x10^{8}W-4.8x10^{7}W=7.82x10^{8}W[/tex]

The correct solution, verified by a classmate and the answer key, is 5.3kW

What have I done incorrectly?