Question

In a hostel of 50 girls, there are food provisions for 40 days. If 30 more girls join the hostel, how long will these provisions last?

Answer 1

\[\text{ Let x be the number of days with food provisions for 80 (i . e . , 50 + 30) girls }  .\]

Number of girls	50	80
Number of days	40	x

\[\text{ Since the number of girls and the number of days with food provisions are in inverse variation, we have: } \]
\[ 50 \times 40 = 80x\]
\[ \Rightarrow x = \frac{50 \times 40}{80}\]
\[ = \frac{2000}{80}\]
\[ = 25\]
\[ \text{ Thus, the required number of days is }  25 .\]