In my haste I used the wrong multiplier for Newcastle - should have been 5 and not 6, so results should be

Newcastle
Outlay $30
Collect 5 x $6.20 = $31.00
Profit $1.00

Morphettville Parks
Outlay $25
Collect 2 x $73.20 = $146.40
Profit $121.20

Doomben
Outlay $22
Collect $nil
Loss $22

Today's totals
Outlay $77
Collect $177.4
Profit $100.40

OVERALL
Outlay $277
Collect $369.60
Profit $92.60
POT 33.4%