The original price of the processor from PC Replacements is \$340.28. The series discount is 10/18, which means a 10% discount followed by an 18% discount.
First, apply the 10% discount:
\[
340.28 \times (1 - 0.10) = 340.28 \times 0.90 = 306.252
\]
Next, apply the 18% discount to the result:
\[
306.252 \times (1 - 0.18) = 306.252 \times 0.82 = 251.12664
\]
Round to the nearest cent:
\[
251.12664 \approx 251.13
\]
The net price from PC Replacements is \boxed{251.13}.
The original price of the processor from PC Upgrades is \$290.28. The series discount is 5/13, which means a 5% discount followed by a 13% discount.
First, apply the 5% discount:
\[
290.28 \times (1 - 0.05) = 290.28 \times 0.95 = 275.766
\]
Next, apply the 13% discount to the result:
\[
275.766 \times (1 - 0.13) = 275.766 \times 0.87 = 239.91642
\]
Round to the nearest cent:
\[
239.91642 \approx 239.92
\]
The net price from PC Upgrades is \boxed{239.92}.
Subtract the net price of PC Upgrades from the net price of PC Replacements:
\[
251.13 - 239.92 = 11.21
\]
The difference between the two prices is \boxed{11.21}.
- Net price from PC Replacements: \boxed{251.13}.
- Net price from PC Upgrades: \boxed{239.92}.
- Difference between the two prices: \boxed{11.21}.