How Many Are Here?

Oh, a merry group of 3 met a merry group of 2
They got together to sing and play
They said, "How many are here today?...3 plus 2 is 5
A merry group of 5 met a merry person 1
They got together to sing and play
They said, "How many are here today?...5 plus 1 is 6
A friendly group of 4 met another group of 4
They said "Let's get together and we'll have so many more"
Someone find the sum and say how many we have today?...
We're a jolly group, a traveling troop of 4 plus 4 is 8
Oh, a merry group of 4 met a merry group of 3
They got together to sing and play
They said, "How many are here today?... 4 plus 3 is 7
A friendly group of 5 met a friendly group of 4
They said "Let's get together and we'll have so many more"
Someone find the sum and say how many we have today?...
We're a jolly group, a traveling troop of 5 plus 4 is 9
Oh, a merry group of 5 met a merry group of 5
They got together to sing and play
They said, "How many are here today?...5 plus 5 is 10
Then everyone danced away, none remained to sing and play
Zero friends were left to say, "How many are here today?"