Classroom A raised 2 x $20 = $<<2*20=40>>40 from two families.
They raised 8 x $10 = $<<8*10=80>>80 from eight families.
They raised 10 x $5 = $<<10*5=50>>50 from ten families.
Altogether, they raised $40 + $80 + $50 = $<<40+80+50=170>>170.
Therefore, they need $200 - $170 = $<<200-170=30>>30 more to reach the goal.
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