Question

f) 60 students in a hostel have food enough for 30 days. If 20 more students join the hostel after 10 days, how long will the remaining food last?

Answer 1

Hello,

10 days

Explanation:

60 étudiants dans un foyer ont assez de nourriture pour 30 jours. Si 20 étudiants supplémentaires rejoignent l'auberge après 10 jours, combien de temps durera la nourriture restante ?

Let say A the quantity of food

60 students in a hostel have food enough for 30 days ==> A=k*60*30

==> k=A/1800

Let say x the duration of the food.

60 students for x days + 20 students for (x-10) days =A

`k*60*x+k*20*(x-10)=A\\`

`(A*60*x)/(1800) +(A*20*(x-10))/(1800) =A\\\\60x+20x-200=1800\\\\80x=1600\\\\x=20\\`

Duration for the 80 students: 20-10=10days