Answer: 36%
Explanation:
Since the price last week, was 4 boxes for $5. Therefore, the price per box will be:
= $5/4
= $1.25 per box
This week they mark a new price at 5 boxes for $4. The price per box will be:
= $4/5
= $0.8 per box
The percent decrease in the price per box this week will be:
= (1.25 - 0.80)/1.25 × 100
= 0.45/1.25 × 100
= 36%
The Percentage decrease is 36%