# 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 result:

t =  17.5 h

#### Solution:

$875 \cdot \ 2=100 \cdot \ t \ \\ \ \\ t=\dfrac{ 875 \cdot \ 2 }{ 100 }=\dfrac{ 35 }{ 2 }=17.5 \ \text{h}$

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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

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