If one person sends the e-mail to two friends, asking each of them to copy the mail and send it to two of their friends, those in turn send it to two of their friends and so on.
How many e-mails would have been sent by the time it did 30 sets?
Welcome to Chat Box...
is your visitor number
I will always welcome your valuable suggestions for this blog..
If You wish to post your own Questions...
send me to atitpshah@gmail.com..
with subject as "question"..
I will post it with your name
Time
is your visitor number
1 comment:
Answer
2147483646
First person sent the mail to 2 persons. Those 2 sent the mail to 2 persons each, total 4 persons. Now, those 4 person sent mail to total 8 persons, then 8 to 16 persons, 16 to 32 persons and so on.... Hence, it a series of 2, 4, 8, 16, 32 upto 30 numbers
It is a Geometric series with common ratio 2 and first number is also 2. Summation of such series is given by A * (Rn - 1) / (R - 1) where
A = First term
R = Common Ratio
n = total numbers
So total number of times mail sent by the time it did 30 sets
= 2 * (230 - 1) / (2 - 1)
= 2 * (1073741824 - 1)
= 2 * 1073741823
= 2147483646
More Puzzles
Post a Comment