From the question;
A gorcery bill of $18.39 is paid with a $20 bill
we are to calculate the change to be collected
This will be done by saying
[tex]\begin{gathered} Change\text{ = \$20 - \$18.39} \\ \text{ \$20.00} \\ \text{ -} \\ \text{\$18.39} \\ ----- \\ =\text{\$1.61} \end{gathered}[/tex]Therefore,
The change to be received is $1.61
