Question

A group of birds are flying in a triangular formation.The birds are arranged in a series of row,with one row behind the other with one lead bird at the front, behind the lead bird there is an equal number of birds on the left hand side of the formation as the right hand half of the formation ,and along each row the number of spaces between adjacent birds is the same,each bird flies with the same speed and there are 9 birds at the back row.hiw many birds are there?

Answer 1

Answer:

5

Step-by-step explanation:

A group of birds are flying in a triangular formation.The birds are arranged in a series of row,with one row behind the other with one lead bird at the front, behind the lead bird there is an equal number of birds on the left hand side of the formation as the right hand half of the formation ,and along each row the number of spaces between adjacent birds is the same,each bird flies with the same speed and there are 9 birds at the back row