# How to determine the cross rate in a triangular arbitrage

I am very confused about what two currencies are to be chosen as the cross rate in a triangular arbitrage.

For example, when the bank quotes are

1. ¥180/£
2. $$1.5/£$$

3. ¥130/$Does the cross rate have to be ¥120/$?

Couldn't it be \$1.38/£?

Can I use any two currencies to calculate the profit?

• It doesn’t matter which rate you treat as the ‘cross rate’ in the same way that there is no one side of a triangle which is more important than the other two. Dec 29 '18 at 21:31