There is hypothetical state between india and pakistan border 'paglapur'.
Here 70 percent of the population have defective eyesight, 75 percent are hard of hearing, 80 percent have sinus trouble and 85 percent suffer from allergies, what percentage (at a minimum) suffer from all four ailments?
10%
100 - [ (100-85)+(100-80)+(100-75) +(100-70)]
=100-(15+20+25+30)
=100-90
