A garrison of 400 men had a provision for 31 days. After 25 days 320 persons re-enforcement leave the garrison. Find the number of days for which the remaining ration will be sufficient?  Choose one:
A) 65 days	B) 30 days	C) 10 days	D) 16 days	E) 18 days
400 --- 31   400 --- 6   80 --- ?   400*6 = 80*x =&gt; x =30 days.   Answer: 30 days
<result>B</result>
A garrison of 400 men had a provision for 31 days. After 25 days 320 persons re-enforcement leave the garrison. Find the number of days for which the remaining ration will be sufficient?