Bulbs and electricity

In the sports hall, 875 identical light bulbs light for 2 hours. How long does it take for 100 such light bulbs to consume the same amount of electricity?

Correct answer:

t =  17.5 h

Step-by-step explanation:

$$\begin{gathered} 875\cdot 2=100\cdot t \\ t={\displaystyle \frac{875\cdot 2}{100}}={\displaystyle \frac{35}{2}}={\displaystyle \frac{35}{2}}\text{ h}=17.5\text{ h} \end{gathered}$$

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Showing 1 comment:

Math student

I can't understand the result. How 875 lighting for2 hours and 100 lighting for 17.5 hour

11 months ago  Like

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