First calculate any implied cross rate to see if any arbitrage
exists.
What is the implied S(U/£) cross rate?
£1.50 = $1.00 ⇔ $1.00 = U120
£1.00 = U80 ⇔ S(U/£) = U80
Credit Agricole has posted a quote of S(U/£)=85 so there is
an arbitrage opportunity.
So how can we make money?
. Buy the £ @ U80; sell @ U85.
Then trade yen for your preferred currency.
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