\(3\times2.5\times1.05=7.5\times1.05=7.875\approx\boxed{7.9}\)
If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up (+1).
If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down (no change).
7.875 ≈ 7.9
