Problem Solving (PS) | Re: In a village of 100 households, 75 have at least one DVD

Here,the maximum households having three will be 55
Now,if we want to get the minimum number of households having three,we need to find at least how many have two of things.
So,At least DVD and cell phone=(75+80)-100=55
At least DVD and MP3=(75+55)-100=30
At least cell and MP3 =(80+55)-100=35
now,minimum number=(75+80+55-30-35-55)-100=10
so,the difference is (55-10)=10
Hope it's clear now
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