It's just the inverse ratio.
$1.24 is the cost of converting $1USD to $CAD. $0.81 is the cost of converting $1CAD to $USD.
$1.24 is the cost in CAD to buy 1 USD. 0.81 is the cost in USD to buy 1 CAD, plus banking fees which vary. It is not quite the inverse, there is a spread.





















































