ROUND is not the same as formatting
Showing a cell to two decimal places does not change the number inside it. 10.994 displayed as £10.99 is still 10.994, and a column of them totals as though every hidden third decimal were still present, because it is.
That is why a column of neatly formatted figures can add to a total that is a penny or two off what the displayed numbers say. Nothing is broken; you are adding the real values and reading the rounded ones.
ROUND actually changes the value. Where the pennies have to agree, an invoice, a payroll run, round the values rather than formatting them.
In C2, round each line amount to 2 decimal places and fill down to C5. Put the total of the rounded column in C7.
The grid for this exercise is part of the paid half.
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