Question

A supply of foods last for a week for 20 families. how long would the supply last for 3 more families.?​

Answer 1

Given that,

A supply of foods last for a week for 20 families.

It is required to find the time that  would the supply last for 3 more families.

20 families = 1 week = 7 days

If 3 more families joined, total no of families are now 23.

It means that,

1 family= (20/7) days

Now,

23 family =

$\dfrac{20}{7}\times 23=65.71\ \text{days}\\\\\approx 66\ \text{days}$

So, the supply will last for 66 days.