To find the length of the remaining rod, we subtract the length of the cut piece from the original length of the rod. Original length =43.4m Cut length =3.532m Remaining length = Original length - Cut length Remaining length =43.4−3.532 Let's perform the subtraction: 43.400 (adding zeros to align decimal places for calculation) 3.532 39.868 places. The original length ( 43.4 m ) has one decimal place. The cut length (3.532m) has three decimal places. The measurement with the fewest decimal places is 43.4 m , which has one decimal place. Therefore, our final answer must be rounded to one decimal place. Our calculated exact result is 39.868 . To round 39.868 to one decimal place, we look at the second decimal place, which is 6 . Since 6 is 5 or greater, we round up the first decimal place (8). So, 39.868 rounded to one decimal place is 39.9 . Comparing this with the given options: Option A: 39.9 Option B: 39.8 Option C: 39.868 Option D: 39.87 The correct answer is 39.9 m .