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cindyqtran
- Junior | Next Rank: 30 Posts
- Posts: 21
- Joined: Sun Aug 26, 2007 11:45 am
let nos male rats =40
so female rats = 100-40 =60
let x =nos of rats who died
so .3x = nos of male rats who died
.7x = nos of female rats who died
so death rate (%) of male rats =.3x/40 *100=3x/4
death rate among female rats = .7x/60 *100 =7x/6
so ratio is 3x/4 / 7x/6
=9/14
so ans should be A

















