We are given that Peter buys 12 bunches of bananas for 9.00.
We need to determine how much peter will pay for 8 bunches.
Let us set up proportion now.
12 bunches of bananas for 9.00 = 12 : 9
Let us assume Peter will pay for 8 bunches = $x.
Therefore, 8 bunches of bananas for x = 8 : x.
Setting up proportion:

On cross-multiplying, we get
12x = 9×8
12x = 72.
Dividing both sides by 12, we get

x=6.
Therefore, Peter will pay $6 for 8 bunches.