The stock of grain in a government warehouse lasts 30 days for 4000 people . How many days will it last for 6000 people ?
Let 1 person consume 'x' food in 1 day
1 person 1 day → x
4000 people 1 day →4000x
4000 people 30 days →4000x×30
Total food =4000x×30
Let no. of days be y
6000 people, 1 day →6000x
6000 people, y days →6000xy
Total food =6000xy
So 4000x×30=6000xy
y=4000×306000
y=20days.