Joanna has $<<8=8>>8.
Joanna's brother has thrice as much as Joanna, so he has $8 * 3 = $<<8*3=24>>24.
Her sister has half as much as Joanna, then she has $8/2 = $<<8/2=4>>4.
Together they have $8 + $24 + $4 = $<<8+24+4=36>>36 altogether.
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