Answer: 96 green pens sold
Explanation:
Black = 3 pens
Red = 5 pens
Green = 6 pens
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Black = 7 packs
Red = 2 packs
Green = 4 packs
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Black = 3 x 7 = 21 total pens
Red = 5 x 2 = 10 total pens
Green = 6 x 4 = 24 total pens
Total units for total pens = 21 + 10 + 24 = 55u
55u = 220
1u = 220/55
= 4
24u = 4 x 24
= 96 green pens sold
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96 green pens were sold.