Answer:
a) Geneva
b) £20
Explanation:
Part (a)
First, we need to convert the price of the watch in Geneva from Swiss francs (CHF) to British pounds (£) so that we can compare the prices of the watches in the same currency.
We know that £1 = 1.55 CHF, so we can use this exchange rate to convert the price of the watch (Geneva) from CHF to £:

This means that the watch in Geneva costs 125 British pounds.
Now we can compare the prices of the watches. We know that the watch in Manchester costs £145, and the watch in Geneva costs £125.
Answer to part a) = The cheaper option is clearly the watch in Geneva.
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Part (b)
Now, to find how much it is cheaper by, we can subtract the price of the watch (Geneva) from the price of the watch (Manchester):

Answer to part (b) = The watch in Geneva costs £20 less than the watch in Manchester.
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Summary
- The watch in Manchester costs £145.
- The watch in Geneva costs 193.75 CHF, which is equivalent to £125.
- Therefore, the watch in Geneva is cheaper by £20.48.
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