The manager of a hardware store keeps records of all of the items purchased and sold. The table shows some of the records for Tuesday.

1. Which items were sold at the hardware store on Tuesday? Explain your reasoning.
2. What does -25 mean in this situation?
3. What does -15.00 mean in this situation?
4. On which item did the manager spend the most amount of money? Explain your reasoning.

A vending machine in an office building sells bottled beverages. The machine keeps track of all changes in the number of bottles from sales and from machine refills and maintenance. This table shows the changes for every 1-hour period over one day.

1. What does a positive number in the second column mean in this context? What does a negative number mean in this context?

   time	number of bottles
   8:00–8:59	-1
   9:00–9:59	+12
   10:00–10:59	-4
   11:00–11:59	-1
   12:00–12:59	-5
   1:00–1:59	-12
   2:00–2:59	-2
   3:00–3:59	0
   4:00–4:59	0
   5:00–5:59	-6
   6:00–6:59	+24
   7:00–7:59	0
   service

2. What would a “0” in the second column mean in this situation?
3. Which numbers—positive or negative—result in fewer bottles in the machine?
4. At what time was there the greatest change in the number of bottles in the machine? How did that change affect the number of remaining bottles in the machine?
5. At which time period, 9:00–9:59 AM or 1:00–1:59 PM, was there a greater change to the number of bottles in the machine? Explain your reasoning.
6. The machine must be emptied to be serviced. If there are 40 bottles in the machine when it is to be serviced, what number will go in the second column in the table?