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My friend Asha was throwing a very grand party and wanted to borrow from me 100 wine glasses. I decided to send them through my boy servant Harish. Just to give an incentive to Harish to deliver the glasses intact I offered him $3 for every glass delivered safely and threatened to forfeit $9 for every glass he broke. On settlement, Harish received $240 from me. How many glasses did Harish break?