72 persons have enough food for 7 days . but after one day they decided to finish the food in 3 remaining days . For if they invited more persons how many persons did they invite?

We have been given that

72 persons has enough food for 7days.

After 1 day they decided to finish the food in remaining 3 days.

We need to find number of invitees to finish the food.

After one day there are 72 people and they have food for 6 days.

If people are changed n times, time will change to (1/n) of initial time.

\frac{1}{n}\times 6\ =\ 3n1×6 = 3

Therefore n = 2

Total number of people needed  = n × 72

Total number of people needed = 72×2

Total number of people needed  = 144

Hence the number of invitees = 144 - 72 =72

72 people are invited to finish the food in 3 days

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