A garrison of 400 men had a provision for 31 days. After 28 days 280 persons re-enforcement leave the garrison. Find the number of days for which the remaining ration will be sufficient?  Choose the correct choice from the following answers:
A) 22
B) 28
C) 10
D) 66
E) 23
400 --- 31   400 --- 3   120 --- ?   400*3 = 120*x =&gt; x =10 days   Answer: 10
<result>C</result>
A garrison of 400 men had a provision for 31 days. After 28 days 280 persons re-enforcement leave the garrison. Find the number of days for which the remaining ration will be sufficient?