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Grade 10Electric Current

If I can spend ₹9 per month on electric light and the power is 30 paise per kWh. and I use 5 identical bulbs for 5 hours a day. What should be the power of each bulb?

Profile image of Ishan
7 Years agoGrade 10
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2 Answers

Profile image of yathartha gupta
7 Years ago
Let 1 bulb =x kwh
 Hence,5 bulb=5x kWh
For 5 hours in 1 day = 5×5x = 25x kwh
 In a month =25x ×30 = 750x kwh
At the rate of 30 paisa per kwh the power will be
    750x × 0.30 = 225x rs
According to question ....
            225x = 9
         x = 9÷225
        x = 0.04 kW
     Thus,
                 The power of each bulb will be 0.04 kw
or 40 watt.
 
 
Profile image of Ekta Agrawal
4 Years ago
Let 1 bulb =x kwh
 Hence,5 bulb=5x kWh
For 5 hours in 1 day = 5×5x = 25x kwh
 In a month =25x ×30 = 750x kwh
At the rate of 30 paisa per kwh the power will be
    750x × 0.30 = 225x rs
According to question ....
            225x = 9
         x = 9÷225
        x = 0.04 kW
     Thus,
                 The power of each bulb will be 0.04 kw
or 40 watt.