Answer: B) 5 inches
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Step-by-step explanation:
1 ft = 12 in
9 ft = 108 in ... multiply both sides by 9
9 ft, 9.5 in = 108 in + 9.5 in = 117.5 in
The board's length of 9 ft, 9.5 inches is the same as 117.5 inches.
It's cut into sections of 11.25 inches, so we have (117.5)/(11.25) = 10.44 approximately which rounds down to 10.
Having 10 sections of length 11.25 inches each, takes up 10*11.25 = 112.5 inches so far. That leaves 117.5 - 112.5 = 5 inches as the remaining piece of the board.