Answer
Find out the what is the cost per pound .
To proof
Let us assume that the one banana cost be x.
As given in the question
[tex]2\frac{1}{4}\ pounds\ of\ bananas\ cost\ $1.89[/tex]
[tex]\frac{9}{4} pounds\ of\ bananas\ cost\ $1.89[/tex]
Than the equation becomes
[tex]x =\frac{1.89}{\frac{9}{4}} [/tex]
solving
[tex]x =\frac{1.89}{2.25}[/tex]
x = $0.84(approx)
Therefore the cost of bananas per pound be $0.84(approx) .
Hence proved