Since 1 British Pound is equal to 438.846801511 Sri Lankan Rupees, we could say that n British Pounds are equal to 438.846801511 times n Sri Lankan Rupees. In other words, we could use the following formula:
Sri Lankan Rupees = British Pounds x 438.846801511
For example, let's say that we want to convert 2 British Pounds to Sri Lankan Rupees. Then, we just replace British Pounds in the abovementioned formula with 2:
Sri Lankan Rupees = 2 x 438.846801511
That is, 2 British Pounds are equal to 877.693603022 Sri Lankan Rupees.