One week you tell 3 of your friends a secret. The next week, each of them tells 3 people the secret and the next week each of those people tell 3 more people. So the first week, 3 new people know the secret, the second week 9 new people know the secret, the third week 27 new people know the secret, etc. How many people find out the secret on the 4th week?
Answer:81
Step-by-step explanation:
Given
In first week 3 new people Knows the secret and
in second week 9 new people new the secret
and in the third week 27 new people knows the secret
so we can see that each week new people are increasing as power of 3
i.e. \(3^n\)
where n= no of week
For n=1, it is 3
for n=2,it is 9
for n=3,it is 27
for n=4,it is 81