Final answer:
To find out how much of the board Alan needs to cut off, we can subtract the length of the table from the length of the board. The length of the table is 6 1/2 feet and the length of the board is 7 7/8 feet. Alan needs to cut off 37/8 feet or 4 5/8 feet of the board.
Step-by-step explanation:
To find out how much of the board Alan needs to cut off, we can subtract the length of the table from the length of the board. The length of the table is 6 1/2 feet and the length of the board is 7 7/8 feet. We can represent these as fractions: 6 1/2 = 13/2 and 7 7/8 = 63/8.
To subtract them, we need a common denominator, which is 8, so we convert 13/2 to 26/8. Now we can subtract 63/8 - 26/8 = 37/8. Therefore, Alan needs to cut off 37/8 feet or 4 5/8 feet of the board.