Co23walr

I have got a foreign saving interest of USD 1000 and exchanged it into GBP 780. I found it later that according to the monthly exchange rate, the interest is to be calculated as GBP 800. Could I report GBP 780 as the saving income or GBP 800?

Suppose I have exchanged USD 1270 to GBP 1000. On a later day,GBP 1000 was exchanged to USD1290. Is there a capital gain to be reported? However, if the transactions need to be converted into sterlings to calculate the capital gain, both the proceed and the cost will be GBP1000 (the cost will be a bit higher due to the commission fees). Should I report the loss instead?

I have bought and sold US stocks. To my understanding, the cost and the selling price have to be converted to sterling pound in order to calculate the capital gain. Suppose the gain is USD 100, as different exchange rates are used in converting the cost and selling price, there is a loss of GBP 50 after the conversion. How to report this in the tax form in this case?