To determine the correct old and new prices given a 25% increase, we can use the formula:
\[ \text{New Price} = \text{Old Price} \times (1 + \text{Percentage Increase}) \]
In this case, the percentage increase is 25%, or 0.25 as a decimal.
So, the formula becomes:
\[ \text{New Price} = \text{Old Price} \times 1.25 \]
Now we can check each provided pair of prices:
-
Old price: $200, New price: $270
- New Price = \(200 \times 1.25 = 250\) (not correct)
-
Old price: $15, New price: $18
- New Price = \(15 \times 1.25 = 18.75\) (not correct)
-
Old price: $320, New price: $400
- New Price = \(320 \times 1.25 = 400\) (correct)
-
Old price: $44
- New Price cannot be determined from just the old price; we need a specific new price to check.
Based on these checks, the correct answer is:
- Old price: $320, New price: $400
None of the other pairs properly reflects a 25% increase.