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Total power consumed = 100 + (2 x 60) + 30 = 250 Watts
Consumption in Kwh = $\frac{250}{1000}$ x 70 = 17. 5 Kwh
Cost of electricity = 17.5 x $\frac{40}{100}$ = Ksh 7. 00
johnmulu answered the question on February 20, 2017 at 05:25
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