When 1000 children were inoculated witha certain vaccine,some developed inflamtion at the site of the inoculation and some developed fever.how many of the children developed inoculation but not fever.?
1)880 children developed neither inflamation nor fever
2)20 children developed fever
i guess there is a typo: innoculation should be inflamation. ok, now
from i and ii, fever = 20
nither = 880
so fever + inflamation = 120
so only inflamation = 100