Increase £ 399 by 26.5% rounded to the nearest penny

It is a simple question where finding out the increase of 399 pound by 26.5% is required. The answer needs to be rounded off to the nearest penny.
So
Total amount of increase = 399 * (26.5/100)
                                         = 10573.5/100
                                         = 105.735
So increase of 399 pound by 26.5% gets to = (399 + 105.735) pounds
                                                                       = 504.735 pounds
Noew this amount has to be rounded to the nearest penny and so the amount becomes 504.74 pounds.

$22. if larry's profit were to minimize by one for every hour his store were to be closed, we would subtract 30 by 8.

Idon’t know actually is more difficult