The cross rate between $ and AUD is calculated in the following manner:
Step 1: Multiply the two quotes together (THB will cancel out) to obtain AUD/$: 0.02240 THB/$ * 23.89923 AUD/THB = 0.53534 AUD/$.
Step 2: Take the reciprocal of this result to obtain $/AUD: 1 / 0.53534 AUD/$ = 1.86796 $/AUD
An alternative calculation method is as follows:
Step 1: Take the reciprocal of the THB/$ quote: 1 / 0.02240 THB/$ = 44.64286 $/THB
Step 2: Divide this result by the AUD/THB quote: 44.64286 $/THB / 23.89923 AUD/THB = 1.86796 $/AUD