Final answer:
To determine the maximum width of the mail slot, we subtract the thickness of the envelope from the width of the slot. After considering the given options, the maximum width is found to be 15 inches.
Step-by-step explanation:
To determine the maximum width of the mail slot, we need to consider the dimensions of Joel's envelope. The envelope should fit through the slot without bending, so the width of the slot must be larger than the width of the envelope. Based on the given options, we can calculate the maximum width by subtracting the thickness of the envelope from the width of the slot. Let's go through the options:
- Option a) 12 inches: If the envelope is 0.5 inches thick, the maximum width would be 11.5 inches. This option does not work.
- Option b) 8 inches: If the envelope is 0.5 inches thick, the maximum width would be 7.5 inches. This option does not work.
- Option c) 10 inches: If the envelope is 0.5 inches thick, the maximum width would be 9.5 inches. This option does not work.
- Option d) 15 inches: If the envelope is 0.5 inches thick, the maximum width would be 14.5 inches. This option works as it is larger than the calculated maximum width. Therefore, the maximum width of the mail slot is 15 inches.