Answer :
December = $57
In December, the price was $57, which was $29 less than the price in November then November price was: $57 + $29 = $86
In November, the price of a GizmoPhone was double the price in March. so March: $86 x 2 = $172
answer: the price of a GizmoPhone in March was $172
In December, the price was $57, which was $29 less than the price in November then November price was: $57 + $29 = $86
In November, the price of a GizmoPhone was double the price in March. so March: $86 x 2 = $172
answer: the price of a GizmoPhone in March was $172