Question 772639
If the lamp's regular price was $16, then 
25% off would make it sell for $12
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If the lamp's regular price was $12, then 
25% off would make it sell for $9
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If the lamp's regular price was $8, then 
25% off would make it sell for $6
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If the lamp's regular price was $4, then 
25% off would make it sell for $3
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The largest possible regular price of the lamp is $16