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(a) Power consumed by 5 bulbs = 60 × 5 = 300 W = 0.3 kWh. Time = 10.30 – 7.00 = 3 ½ hrs.
Therefore for the time duration = 0.3 × 3 ½ = 1.05 kWh.
(b) Power consumed in 7 days = 1.05 × 7 = 7.35 kWh. Cost = 7.35 × 0.9 = Ksh 6.62
Mutiso answered the question on October 16, 2018 at 18:18
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