arithmetic - a garrison has provisions for 90 soldiers for 160 days after 100 days 45 more soldiers will join the group for how many more days will the provisions last - skillgun

Actually after 100 days,
If 90 members are there, provisions come for 60 more days (since total 160 days)
But now 135 members are there.
So number of days = (90/135) X 60 = 20 days.