We can let this weeks price = n and create the equation:

n - 0.6n = 179.95

0.4n = 179.95

n = 449.875

Rounding n up to the nearest hundredth, we obtain $449.88.

Answer: E

I don't understand why the strategy "part/whole = percent/100" works in this question when I set it as 179.95/x = 40/100 but not when I write it as 179.95/x = 60/100.

Thank you

Because you did the wrong assumption.

If the actual price, that can be easily rounded for easier calculations to 180, is 60% off of the regular price

This means that 180 is the actual sell price at 40%. In other word, if 180 was reduced by 60% it is the rest or 40%

Translating this problem in a single operation

180 is the 40% of the price x that we DO NOT know

\(180=0.4x\)

\(x=\frac{180}{0.4}=450\) rounded

ONE single simple operation and you have solved the question. The explanations above are quite good but just wording

I hope this helps