Out on my street, there are a certain number of pigeons sitting on telephone poles. If there were exactly 2 pigeons sitting on each telephone pole, then 1 pigeon would have no space to sit on. If there were exactly 3 pigeons sitting on each telephone pole, then there would be 1 telephone pole with no pigeons on. How many pigeons were there?

1 answer

Let x = # of poles

2x + 1 = 3(x_1)

2 pigeons per pole with 1 pigeon

3 pigeons per poles with 1 less pole.

2x + 1 = 3x -3
x = 4 poles

You have 2 pigeons per pool = 8 pigeons + one left over = 9 pigeons.

3 pigeons per pole = 9 pigeons.

It looks like we have nine pigeons.