Question

Safina invites two friends to a party. Each of those friends invites two more friends, and so on. How many friends are invited to Safina’s party after five rounds of invitations?

Answer 1

After the first round, Safina has 2 friends.
After the second round, there are 2 x 2 = 4 friends.
After the third round, there are 4 x 2 = 8 friends.
After the fourth round, there are 8 x 2 = 16 friends.
After the fifth round, there are 16 x 2 = 32 friends.

So, after five rounds of invitations, there will be a total of 32 friends invited to Safina's party.