<PRE><B>Question 1091000</B>
510/3 = 170
170 x 4 = 680 this is how much he paid
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510 x 2/3 = (510 x 2)/3 = 340 this is how many he sold at 2 for 3
(340/2) x 3 = 480 He got 480 for 2/3 of them.
510 - 340 = 170 These he sold at 5 for 6.50
(170/5) x 6.50 = 221 
Add what he got:  480 + 221 = 701
And he paid total: . . . . . 680
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He made a profit of . . . . . 21
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